A. At the moment shown in the figure, the movement direction of P particles is upward, and the waveform will shift to the right, so it is known that the propagation direction of the wave is along the positive direction of the X axis, so A is correct.

B, as can be seen from the figure, the equilibrium positions of P and A are half a wavelength apart, and the vibration situation is always opposite, so when the particle P is at the lowest point, the particle A must reach the highest point. So, B is wrong.

According to mathematical knowledge, the distance between the equilibrium positions of A and B is equal to 1.3 λ. When the particle P is at the lowest point and A reaches the highest point, the particle B must be below the X axis, so D is correct.

So choose AD.