The Velocity of an Object with Respect to Reference Frame

Multiple Choice

The velocity of an object with respect to reference frame A is equal to

A) the velocity of the object with respect to reference frame B added vectorially to the velocity of reference frame A with respect to reference frame B.
B) the velocity of the object with respect to reference frame B added vectorially to the velocity of reference frame B with respect to reference frame A.
C) Both of the first two responses are correct.
D) Neither of the first two responses is correct.