Deck 2: Nokia Border Gateway Protocol

Question 1

What is the OUI field of the MAC address for IPv4 multicast address?

A) 00-01-5e
B) 00-01-5f
C) 01-00-5e
D) 01-00-5f

Answer 1

01-00-5e

Question 2

An Alcatel-Lucent 7750 SR is unable to locate a multicast source address in the multicast forwarding table. However, the source address is available in the unicast forwarding table. Which statement best describes the default RPF check behavior of the 7750 SR?

A) The RPF check will fail as PIM relies exclusively on the multicast forwarding table by default
B) The RPF check will not fail, as by default PIM uses the multicast forwarding table first for RPF check, if not found in the multicast forwarding table then refers to unicast forwarding table
C) The RPF check will not fail as PIM uses only the unicast forwarding table by default
D) The RPF check will fail as the RPF check requires that the source address be present in both the unicast and multicast forwarding table
E) Not enough information is provided to answer the question

Answer 2

The RPF check will not fail as PIM uses only the unicast forwarding table by default

Question 3

Which of the following statements is false regarding BSR and RP?

A) A router may be both a candidate-BSR and candidate-RP
B) A router configured as a candidate-BSR may also be configured as a static RP
C) A router configured as a candidate-RP may be also be configured as a static RP
D) A converged multicast network with BSR may have multiple routers elected as BSRs
E) A converged multicast network with BSR may have multiple routers elected as RPs

Answer 3

A converged multicast network with BSR may have multiple routers elected as BSRs

Question 4

Refer to the configuration exhibit. Channel 239.1.1.1, 239.1.1.2, 239.1.1.3 and 239.1.1.5 have already been established. What will happen when this router receives two IGMP reports to join group 239.1.1.4 and 239.1.1.8?

A) Channel 239.1.1.4 will be established while 239.1.1.8 will not
B) Channel 239.1.1.8 will be established while 239.1 1.4 will not
C) Both of these two channels will be established
D) Neither of these two channels will be established

Question 5

Which MAC address will the IPv4 multicast address 233.103.42.11 be translated to?

A) 01-00-5e-66-3a-6b
B) 01-00-5e-75-2a-0b
C) 01-00-5e-67-2a-0b
D) 00-01-5e-a1-2a-6b
E) 00-01-5e-67-2a-0b
F) 00-01-5e-76-2b-cc

Question 6

Choose the statements that describe Bootstrap Router mechanism. (Choose three)

A) It is a mechanism to distribute RP-set information dynamically
B) The bootstrap router gets and propagates RP information via multicast messages
C) The bootstrap router gets and propagates RP information via unicast and multicast messages
D) BSR relies on timers to discover that an RP-Candidate router is no longer available
E) For BSR to work, every router in the multicast network should be configured as BSR candidate

Question 7

Which of the following is a reason why using unicast flows to send data to multiple receivers is not a scalable solution?

A) The resources required by the sending device increases with each new receiver that is added
B) Unicast is based on TCP which is not scalable
C) Servers cannot deliver multiple simultaneous unicast flows
D) Routers do not forward broadcast traffic

Question 8

An end station receiving a broadcast packet will always process the data up to at least which layer of the OSI stack?

A) Layer 1
B) Layer 2
C) Layer 3
D) Layer 4
E) Layer 7

Question 9

Refer to the exhibit. Which router is this screen capture taken from?

A) Any router in the PIM multicast domain
B) Only from the Candidate-RP
C) Only from the Candidate-BSR
D) Only from the elected BSR

Question 10

Four routers in a domain are configured as BSR candidate. Router A is configured with a BSR priority of 10, Router B is configured with a BSR priority of 100. Router C and Router D are at the default value. Router D has the highest IP address. Which router will be elected the PIM BSR?

A) Router A
B) Router B
C) Router C
D) Router D

Question 11

Refer to the exhibit. The switch is not igmp-snooping/proxy capable. What will happen if host 2 issues an IGMP report to join a group?

A) Both Router A and Router B will get this IGMP report and Router B will propagate a PIM join towards the core network
B) Both Router A and Router B will get this IGMP report and both of them will propagate a PIM join towards the core network
C) Only Router A will get this IGMP report and Router A will propagate a PIM join towards the core network
D) Only Router A will get this IGMP report and as Router A is not PIM DR, so no further action

Question 12

Which of the following data delivery models are most applicable to multicast data delivery? (Choose two)

A) One to one
B) Many to all
C) One to many
D) Many to many
E) One to all

Question 13

When a BSR message with a higher priority is seen, will a new BSR election occur?

A) No, the new election only occurs when the elected BSR fails
B) Yes, after a bootstrap message wait interval
C) Yes, immediately
D) Depends on the local configuration of whether to allow the new election or not

Question 14

How do the routers in the PIM domain become aware of the address of the elected BSR?

A) It is unicast to them
B) It is flooded through the network in a bootstrap message
C) It is preconfigured on all routers
D) It is flooded through the network in the PIM Hello

Question 15

Which of the following statements are true? (Choose three)

A) A multicast network may have only one source and one receiver segment
B) A multicast network may have one source and multiple receiver segments
C) A multicast network cannot have more than one source segments
D) A multicast network may have multiple source and multiple receiver segments
E) A multicast network cannot have more than one receiver segments

Question 16

Which of the following statements is false?

A) For multicast delivery, the source will send a single copy of each packet regardless of the number of receivers
B) For unicast delivery, the source will send a single copy of each packet regardless of the number of receivers
C) For broadcast delivery, the source will send a single copy of each packet regardless of the number of receivers
D) For anycast delivery, the source will send a single copy of each packet regardless of the number of receivers

Question 17

Which of the following is true regarding the IPv4 multicast address format?

A) The first 3 bits of the address set to '110'
B) A value between 223.0.0.0 and 239.255.255.255
C) The first 4 bits of the address set to '1111'
D) A subnet mask to indicate the network and host portion of the address
E) The first 4 bits of the address set to '1110'

Question 18

Refer to the configuration exhibit. Which of the following statements is true?

A) 2 static RP's cannot be configured on the same device
B) 10.10.10.24 will be RP for 230.1.1.1 and 10.10.10.66 will be RP for 234.1.1.1
C) 10.10.10.24 will be RP for 234.1.1.1 and 10.10.10.66 will be RP for 230.1.1.1
D) 2 static RP's both with override cannot be configured on the same device

Question 19

Refer to the exhibit. Which one of the following descriptions is correct, assuming that all the IGMP join, PIM join and multicast traffic are for the same multicast group?

A) IGMP is enabled on Router A and B's interfaces facing the switch. PIM is not enabled on Router A and B's interfaces facing the switch. IGMP snooping is enabled on the switch.
B) IGMP snooping is not enabled on the switch.
C) PIM is enabled on Router A and B's interfaces facing the switch.

Question 20

How does a Candidate-RP send its information to the BSR?

A) Using PIM address 224.0.0.13
B) It is unicast to all the BSR candidates
C) It is flooded by all PIM routers
D) It is unicast to the elected BSR

Question 21

What is the function of the MDT?

A) It is how PIM neighbors become aware of each other
B) It is how receivers signal the source
C) It is the path to the RP
D) It is the multicast data forwarding path
E) It is the path to the DR

Question 22

IGMP version 3 Host Membership Queries are sent with a TTL of 1 to which of the following addresses?

A) 224.0.0.0
B) 224.0.0.1
C) 224.0.0.2
D) 224.0.0.13
E) 224.0.0.22

Question 23

What is the destination address for MLDv2 report?

A) FF02::1
B) FF02::2
C) FF02::16
D) The specific multicast group address which the host is interested in

Question 24

Which of the following ranges is reserved for IPv6 SSM multicast address?

A) FF1X::/16
B) FF3X::/16
C) FF3X::/96
D) FF7X::/16

Question 25

Refer to the following exhibit. Assuming all links have an equal metric in the IGP, where will the Shared Path Tree be built when Receiver 3 joins the multicast group?

A) Router G-E-C
B) Router G-E-C-A
C) Router G-E-D-B-A
D) There is insufficient information to answer

Question 26

How does IGMP snooping eliminate multicast flooding on the LAN?

A) The switch populates multicast source addresses into the forwarding table
B) The switch acts as an IGMP proxy for the receiver
C) The switch inspects IGMP messages between receivers and routers and populates the forwarding table with active multicast group addresses
D) The switch inspects all multicast traffic between receivers and routers and populates the forwarding table with active multicast group addresses

Question 27

What impact will an asymmetric IGP routing topology have on the PIM RPF check?

A) The PIM RPF check may fail since traffic from the source may arrive on one interface while the IP route to the source may point to another interface on the PIM router
B) PIM does not work in an asymmetric topology and therefore the RPF check will not be done
C) There will be no impact since the shared and source path trees are built from the receiver to the source
D) There is not enough information provided to answer the question

Question 28

How many multicast groups may a single receiver join at any one time?

A) 1
B) 2
C) 4
D) 256
E) As many as the operating system and software allow

Question 29

Where is the best placement of the Rendezvous Point in a PIM SSM network?

A) As close as possible to the multicast source
B) The Rendezvous Point is not required in a PIM SSM network
C) In the redundant core
D) As close as possible to the receiver
E) The Rendezvous Point can be positioned at any router without impact

Question 30

Refer to the following configuration exhibit. How many interfaces have receivers joining group 239.1.1.1?

A) 1
B) 2
C) 3
D) There is insufficient information to answer

Question 31

Which two of the following addresses should not be used in a multicast network at the same time?

A) 239.99.12.35
B) 237.87.12.35
C) 231.57.12.35
D) 229.227 12.35
E) 228.139.12.35

Question 32

In IPv6 multicast ASM mode, which of the following methods cannot be used to obtain the RP address?

A) Static
B) Router solicitation message
C) Bootstrap message
D) Embedded RP

Question 33

Which of the following multicast packets can be forwarded on the Internet?

A) A multicast packet destined to FF70:: 1234
B) A multicast packet destined to FF1E:: 1234
C) A multicast packet destined to FF02:: 1234
D) A multicast packet destined to FF3A:: 1234

Question 34

What is the purpose of GLOP addressing?

A) Allocate each AS a unique range of Inter-domain multicast addresses
B) Define an addressing structure for inside a domain
C) Provide a solution for the depletion of addresses
D) Eliminate the problem of IP multicast addresses overlapping when converted to multicast MAC addresses

Question 35

Refer to the following exhibit. Assuming all links have an equal metric in the IGP, where will Source Path Tree have been created if Receiver 2 and Receiver 3 have joined the multicast group and the source is sending and the switchover has occurred? (Choose two)

A) Router F-D-B-A
B) Router G-E-C-A
C) Router C-E-D-B-A
D) Router G-E-C
E) Router F-D-E-C

Question 36

What is the IPv6 Multicast Address range?

A) FF00::/8
B) FF00::/16
C) FE00::/8
D) FE00::/16

Question 37

The network administrator of 2001:DB8:FEED::/64 wants to embed an RP for the network and the RP's address is 2001 :DB8:FEED::7. Which of the following multicast address ranges would suit this purpose? (The exhibit of Group-to-RP Mapping is just for your reference)

A) FF7x:730:2001:DB8:FEED::/96(x is scope)
B) FF7x:730:2001:DB8:FEED::/80(x is scope)
C) FF7x:740:2001:DB8:FEED::/96(x is scope)
D) FF7x:740:2001:DB8:FEED::/80(x is scope)

Question 38

Refer to the exhibit. According to the PIM configuration on SR-3, can the receiver in the diagram receive multicast traffic from the source for group FF70:340:2001::1000? Assume all the other configurations are correct.

A) Yes. The configuration of PIM is correct and the receiver should get traffic from the source
B) No. The configuration of PIM is no problem, but the scope of the group address used to send traffic is wrong
C) No. As the "rpf6-table" command is missing
D) No. As the embedded-rp group-range is wrong

Question 39

Refer to the configuration exhibit. What will happen when this router receives an IGMPv3 exclude none report for group 232.1.1.1?

A) The router will propagate a (*, 239.1.1.1) join towards RP if it exists
B) The router will randomly pick a source from 192.168.1.1 and 192.168.1.2 and send an (S, G)join towards the source
C) The IGMPv3 report will be dropped and a log about misconfiguration will be generated
D) The router will send a PIM (192.168.1.1,232.1.1.1) Join

Question 40

What is the destination address for MLDv2 general query?

A) FF02::1
B) FF02::2
C) FF02::16
D) The multicast group address which the router assumes its hosts might have interest in.

Question 41

An IGMP version 3 receiver signals EXCLUDE mode with an empty EXCLUDE list. What does this indicate?

A) This is the initial join message and exclusions of sources will follow
B) It is willing to receive traffic from any source
C) This is the initial join message and a selection of source will follow
D) This is the way it indicates it is leaving the group

Question 42

Which of the following commands will verify the PIM DR on an interface on the Alcatel-Lucent 7750 SR?

A) Show router pim status
B) Show router pim neighbor
C) Show router pim interface
D) Show router pim statistics

Question 43

What multicast component has no function at all in a PIM SSM network?

A) The PIM routing protocol
B) SSM translation on access multicast router
C) The RP
D) IGMP snooping
E) IGMP Querier

Question 44

Refer to the following exhibit. PIM is using the unicast table for RPF-check and the interface IGP metrics are shown. What will happen when Router B receives the multicast packet on its interface facing Router A?

A) Discard the multicast packet as RPF-check fails
B) Forward the multicast packet to Router D (RP) according to its routing table
C) Forward the multicast packet out of all the interfaces in its (*,239.1.1.1) entry's outgoing interface list
D) Forward the multicast packet out of all the interfaces in its (192.168.1.1,239.1.1.1) entry's outgoing interface list

Question 45

Which MDT types are used in a Sparse Mode network? (Choose two)

A) Shared Path Tree
B) Source Path Tree
C) Spanning Tree
D) Special Path Tree
E) Switchover Path Tree

Question 46

Which of the following statements best describes the behavior seen in the network when a receiver joins a multicast channel in the PIM ASM network shown in the exhibit?

A) Both Router B and Router C will propagate a PIM (*, G) Join to the RP when a receiver joins
B) Only Router B will propagate a PIM (*.G) Join to the RP when a receiver joins
C) Only Router C will propagate a PIM(\G) Join to the RP when a receiver joins
D) Depends on the next hop for RP in Router D's RPF table

Question 47

Select the statements that relate to the Shared Path Tree. (Choose three)

A) The RP is the root of the tree
B) The multicast source is the root of the tree
C) It is represented by (*, G) entries
D) It is represented by (S, G) entries
E) The path between receiver and source is always the shortest path
F) It is always created as a result of switchover
G) It is the initial forwarding path created

Question 48

Refer to the following exhibit. Assume all links have an equal metric in the IGP. Receiver 2 and Receiver 3 have joined the multicast group and the source is sending. Where will the Shared Path Tree have been created before switchover? (Choose two)

A) Router G-E-C
B) Router F-D-E-G
C) Router F-D-E-C
D) Router C-A
E) Router F-D-B-A
F) Router G-E-C-A
G) No Shared Path Tree will have been created

Question 49

When forwarding a multicast frame, normal behavior for a LAN switch (without IGMP snooping enabled) is to forward the frame as if it were:

A) A unicast frame with a known destination in the forwarding table
B) A unicast frame with an unknown destination in the forwarding table
C) A unicast frame with a known source in the forwarding table
D) A unicast frame with an unknown source in the forwarding table

Question 50

How does the RP get the first multicast data packet from source?

A) Via the Source Path Tree
B) Via a Register Message which encapsulates the multicast traffic
C) Via a Bootstrap Message which encapsulates the multicast traffic
D) Via the Shared Path Tree

Question 51

The first actions of a router after enabling PIM on the interfaces will be:

A) BSR elections followed by DR elections
B) DR elections followed by PIM Hello messages
C) DR elections followed by BSR elections
D) BSR elections followed by PIM Hello messages
E) PIM Hello messages followed by BSR elections
F) PIM Hello messages followed by DR elections

Question 52

Which of the following configuration steps are mandatory for IPv4 PIM ASM to work? (Choose two)

A) Configure PIM on core and source facing interfaces
B) Configure PIM on access facing interfaces
C) Configure RP statically or via BSR
D) Create and apply register and join policies
E) Define the rpf-table

Question 53

Refer to the following exhibit. The interfaces' IGP metric is as shown and PIM is using unicast table for RPF-check. What will happen when Router B receives the register message on its interface facing Router A?

A) Discard the register message as RPF-check fails
B) Forward the register message to Router D (RP) according to its routing table
C) Forward the register message out of all the interfaces in its (", 239.1.1.1) entry's outgoing interface list
D) Forward the register message out of all the interfaces in its (192.168.1.1, 239.1.1.1) entry's outgoing interface list

Question 54

How many responses should be received if IGMP version 3 is in use and a router sends a Query to a specific multicast group that has 6 active receivers on the local broadcast domain?

A) 1
B) 2
C) 6
D) 7
E) It will be random

Question 55

What is the position of the router shown in the exhibit?

A) The RP
B) The first hop router from the source
C) The router where the Source and Shared Path Trees diverge
D) An upstream router from the diverging router on the Shared Path Tree

Question 56

When forwarding a multicast frame, the normal behavior for a LAN switch with IGMP snooping enabled is to forward the frame based on the similar rules as if it were:

A) A unicast frame with a known destination in the forwarding table
B) A unicast frame with an unknown destination in the forwarding table
C) A unicast frame with a known source in the forwarding table
D) A unicast frame with an unknown source in the forwarding table

Question 57

Which of the following commands will verify, either directly or indirectly, if PIM is configured on an interface on the Alcatel-Lucent 7750 SR? (Choose two)

A) show router pim interface
B) show router pim status detail
C) show router pim status
D) show router interface detail

Question 58

Who periodically sends IGMP Host Membership Queries?

A) The router elected as Querier on a LAN
B) The first host to expire their local suppression timer
C) Only the multicast enabled hosts on a LAN
D) All routers on a LAN
E) All multicast enabled routers on a LAN

Question 59

Refer to the following exhibit. Assume all links have an equal metric in the IGP. Receiver 2 and Receiver 3 have joined the multicast group and the source is not sending. Where will the Shared Path Tree have been created? (Choose two)

A) Router G-E-C
B) Router F-D-E-G
C) Router F-D-E-C
D) Router C-A
E) Router F-D-B-A
F) Router G-E-C- A
G) No Shared Path Tree will have been created

Question 60

Four routers share a multi-access network. Router A is configured with a PIM DR priority of 10, Router B is configured with a PIM DR priority of 100, Router C and Router D are at the default value. Router D has the highest IP address. Which Router will be elected the PIM DR?

A) Router A
B) Router B
C) Router C
D) Router D

Question 61

Why should the anycast RP address not be the system address of a router?

A) 7750 SR configuration does not permit using the system address for an anycast address
B) The system address of a router has to be a unique address within a domain while the anycast address is configured on multiple routers within the domain
C) PIM will not be able to establish its signaling sessions if the anycast address uses the system address
D) None of the above

Question 62

Which of the following are mandatory functions of a multicast receiver on a multicast network using IGMP version 2? (Choose two)

A) Report their multicast group membership to their local router
B) Signal their local router as they join and leave multicast groups
C) Generate feedback to the network or source
D) Listen for announcements advertising available sessions from the source
E) Generate multicast data to the group

Question 63

Which statement best describes the impact of an RP failure in a PIM ASM network?

A) All the existing multicast traffic will be stopped immediately as PIM ASM network must have an RP in order to transmit all the multicast traffic
B) The multicast traffic will be impacted, but not immediately. Multicast routers will not discover the RP failure until the timer expires and the multicast traffic flow will be stopped.
C) No impact at all as RP is not required in a PIM ASM network
D) The traffic will not be impacted if the multicast traffic flows have already been established and the traffic flow does not involve the RP in the path

Question 64

Which of the following statements about MLD protocol is true?

A) All MLD messages are sent with interface global IPv6 address
B) MLDv3 is similar to IGMPv3 which can include/exclude the source ip address for specific groups
C) MLD messages are a subset of ICMPv6 messages
D) By default, MLD messages hop limit is set to 255

Question 65

Which of the following statements is true regarding BSR and RP?

A) The same router cannot be configured as a BSR candidate and as a static RP
B) The same router cannot be a candidate-RP and a BSR-candidate at the same time
C) There is only one active RP in a multicast routing domain at anytime
D) There is only one elected BSR in a multicast routing domain at anytime

Question 66

What is the position of the router shown in the exhibit?

A) The first hop router from the source
B) The RP
C) One router upstream on the Shared Path Tree from the diverging router
D) The last hop router from the source

Question 67

Which of the following PIM messages is sent to RP via unicast?

A) (*, G) Join/Prune
B) (S, G) Join/Prune
C) Register
D) Candidate-RP-Advertisement

Question 68

If the access network supports IGMP version 2 only, what additional configuration is required to enable the SSM model?

A) IGMP snooping
B) IGMP compatibility mode support
C) IGMP version 2 to IGMP version 3 translations
D) IGMP (*, G) Join to PIM (S. G) Join translation
E) PIM ASM to PIM SSM translations

Question 69

Select the statements that relate to the Source Path Tree in ASM. (Choose three)

A) The RP is the root of the tree
B) The multicast source is the root of the tree
C) It is represented by (*, G) entries
D) It is represented by (S, G) entries
E) The path between receiver and source is always the shortest path
F) The Source Path Tree cannot be created without the RP
G) It is the initial forwarding path created

Question 70

Refer to the exhibit. Who will be the RP for group 239.1.34.92?

A) 10.10.10.24 since Dynamic has higher priority than Static
B) 10.10.10.66 since 239.0.0.0/8 is more specific than 224.0.0.0/4
C) Both since 239.1.34.92 is part of both ranges
D) It depends on the setting of the override parameter
E) Neither since this presents a conflict

Question 71

Refer to the following exhibit. Choose the best answer that describes the multicast LAN.

A) There are no active sources in the network
B) There is one active source for 239.1.1.1 and two active sources for 239.2.2.2
C) The devices on sap 1/1/4 and sdp 1000:500 have issued joins for 239.1.1.1
D) There is a router on sdp 1000:500

Question 72

Which of the following statements about Mrouter port is false?

A) Mrouter port is indicated by (**) entry in the MFIB
B) Mrouter port can be configured manually
C) A port on which any type of IGMP message is received will be set as an mrouter port
D) IGMP reports will only be forwarded out of mrouter ports once igmp-snooping is enabled in the vpls service

Question 73

Refer to the following exhibit. Assume all links have an equal metric in the IGP. Receiver 2 has joined the multicast group and the source is sending. As a result of Router F switching to the Source Path Tree, what message will be generated by Router D in the direction of Router E?

A) PIM(*, G)Join
B) IGMP(*, G)Join
C) PIM Hello
D) PIM (S, G)RP-bit prune
E) PIM (*, G)RP-bit prune

Question 74

Refer to the following exhibit. Assume all links have an equal metric in the IGP. Receiver 2 has joined the multicast group and the source is sending. After the switchover of Router F, will a branch of the Shared Path Tree still exist between Router D and Router E?

A) Yes. As it is maintained by the PIM hellos, it will exist until Router D or Router E is PIM disabled
B) Yes, it will exist until the source stops sending multicast traffic
C) Yes, it will exist until Router D prunes itself from the shared path tree
D) No. Only Source Path Trees will remain

Question 75

Refer to the configuration exhibit. Channel 239.1.1.11239.1.1.2, 239.1.1.3 and 239.1.1.5 have already been established. What will happen when this router receives a IGMP report to join group 239.1.1.6?

A) The router will tear down channel 239.1.1.3 as it's non-mandatory and establish a new channel for 239.1.1.6
B) The router will tear down either channel 239.1.1.1 or 239.1.1.2 as they are low class and establish a new channel for 239.1.1.6
C) No existing channel will be torn down and the new channel for 239.1.1.6 will be established as there is enough resource
D) The new channel 239.1.1.6 won't be established and a log will be generated

Question 76

Which of the following PIM messages are sent towards RP? (Choose two)

A) (*, G) Join/Prune
B) (S.G) Join/Prune
C) Register Stop
D) (S, G, rpt) Join/Prune

Question 77

What is the embedded RP for group FF7E: 130:2000:2001:2002:2003:: 1000? (The exhibit of Group-to-RP Mapping is just for your reference)

A) 2000:2001:2002:2003::1
B) 2000:2001:2002:2003::3
C) 2000:2001:2002::1
D) 2000:2001:2002::3

Question 78

What is the Solicited-node multicast address for host 2001:1000:2000:3000::2001:2002:2003?

A) FF02::FF02:2003
B) FF02::FE02:2003
C) FF02::FF:FE02:2003
D) FF02::1:FF02:2003

Question 79

How often will a router issue IGMP Host Membership Reports for group 224.0.0.2?

A) Never
B) 30 seconds
C) 60 seconds
D) 120 seconds
E) 260 seconds
F) A router will never join this group

Question 80

An IGMP version 3 receiver signals INCLUDE mode with an empty INCLUDE list. What does this indicate?

A) It is willing to receive traffic from all sources
B) It is willing to receive traffic from any source
C) This is the initial join message and a selection of source will follow
D) This is the way it indicates it is leaving the group