[单选题]
A wave travels on a a5vzpfbn-zc;97v 3q dr ;mbapv1aipb3d*;y;i: 6t. el ;vnyepope as shown, where $P$ is a point on the rope halfway between the equilibrium position and the maximum displacement.
Which is correct about the direction and magnitude of the velocity of point $P$ after half a period compared to the shown position?
A. Direction Up;Magnitude Increases
B. Direction Up;Magnitude Same
C. Direction down;Magnitude Decrease
D. Direction down;Magnitude Same