Wave propagation 4

The above top is a graph showing the displacement of a wave at a particular instant, which is propagating to the right, as a function of position $x$ . The speed of the wave is $8$ m/s. Which of the $4$ graphs $A$ , $B$ , $C$ and $D$ is appropriate for the displacement at the position $x=4 \text{ m}$ as a function of time passing from this moment on?