物体在平面内做曲线运动，从t=0时刻起，在x方向的位移图象和y方向的速度图象如图所示，则

A．物体的初速度沿x轴的正方向

B．物体的初速度大小为5m/s

C．物体在t=2s时的速度大小为0

D．物体所受合力沿y轴的正方向

--- Hi, Tom. Any idea where Jane is?

--- She _________ in the classroom. I saw her there just now.

A．shall be

B．should have been

C．must be

D．might have been