Question

A cat runs in a straight line. The figure below shows a graph of the cat's position as a function of time.

Which of the following statements about the cat's motion must be true?
A. At point c, the cat has returned to the place where it started.
B. The cat's speed is zero at points a and c.
C. The cat's velocity is zero at point b.
D. The cat reverses the direction of its velocity at point b.