H.264 video divides images into three types of frames: I, P, and B. Among them, frame a uses inter-frame coding, and frame b uses intra-frame coding. Which of the following statements about types a and b is correct?

H.264 video divides images into three types of frames: I, P, and B. Among them, frame a uses inter-frame coding, and frame b uses intra-frame coding. Which of the following statements about types a and b is correct?
A . B, P
B . P, I
C . I, P
D . I, B

Answer: B