Jinhua coordinate recruitment

The wavelength read out from the diagram is λ=20m, and the period is t = λ V = 20m/SS =1s.

Time t=6s=6T. Because of the periodicity of waves, the waveforms overlap at every integer multiple period, so the waveforms of t=6s and t=8s are the same. Therefore, it is only necessary to analyze 14T forward when t=8.25s, and it is concluded that the particle with x= 10m passes through the equilibrium position downwards, that is, y=0cm, and the velocity direction is in the negative direction of the y axis.

Therefore, choose: B.