甲、乙两个质量相同的物体受到竖直向上的拉力作用，从同一高度向上运动，它们的运动图象如图所示，则下列说法正确的是

A．在时间内甲的加速度越来越大

B．在时刻两物体的高度相同

C．在时刻甲所受拉力的瞬时功率大于乙所受拉力的瞬时功率

D．在时刻甲所受的拉力大于乙所受的拉力

Shirley had to buy ________ these CDs because she didn't know which one to take. [ ]

A. all

B. none

C. each

D. both