In a sine wave position, of different particles at time t = 0 is shown in the figure. The equation for this wave if it is travelling along positive x–axis can be

At t = 0, x = 0 displacement y = 0
Therefore, option (A) and (B) may be correct.
Secondly slope at x = 0 at t = 0 is positive
i.e., particle velocity is in negative y–direction because particle velocity
= – (slope) (wave speed).
So, particle at x = 0 travelling in negative y–direction.