[单选题]
A wave travels on a r4l gu0d+nfn u:d)2mrf 0eeo-aops *yj.r/l7ng + msr5yne 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
