A lifeguard sees a beach ball floating on the crest of an incoming wave. The ball briefly disappears, then reappears in the same spot just as the next
wave starts rising. What is probably the main reason that this is happening?

A. the relatively long period of the wave
B. the orbit of the water in the passing waves
C. a wave amplitude that is taller than the ball
D. the low velocity of the wave carrying the ball