Which Statement Is Correct

Multiple Choice

Which statement is correct?

A) The netdate command and the ntpd use the same port
B) The Network Time Protocol uses port 123, TCP
C) A Stratum 16 server is one that sets it's time by some external reference clock, such as an atomic clock.
D) NTP aims at correcting the system time without sudden bigger changes.
E) /etc/clock.conf is the NTP daemon configuration file.