Question

The phrase circular orbital motion refers to what type of water motion?
A. Deep ocean currents
B. Tidal flow
C. Wave action
D. Surface currents

my answer is c.

Answer 1

You are correct, although in fact the question is not very well phrased. Water particles in deep water waves (water depth greater than half a wavelength) describe circular orbital paths, decreasing exponentially in radius with depth. The particle velocity is up on the front (as any surfer knows), forward at the crest, down on the back, back in the trough.

Answer 2

Thanks!