题目

阅读理解  阅读短文，然后根据其内容选择正确答案。 An elephant and a monkey were arguing. “Look, how big and strong I am!” The elephant said. The monkey disagreed, “Look, how fast I can run and climb! Can you?” At last they asked a wise tiger, “Which is better—to be strong or to be quick?” The tiger said, “Go across the river and pick the fruit on that tree for me, then I can tell.” So they went to the river, but the water ran fast and the monkey was afraid. “Get on my back,” said the elephant proudly, “I shall carry you.” Soon they crossed 如图所示，一粗糙的水平传送带以恒定的速率v1沿图示方向运行，传送带的左、右两侧各有一与传送带等高的光滑水平面，一物体以速率v2沿水平面分别从左、右两端滑上传送带，下列说法正确的是                  （    ）     A．若v2<v1，物体从右端滑上传送带，则物体不可能到达左端     B．若v2>v1，物体从右端滑上传送带，则物体一定能够到达左端     C．若v2<v1，物体从左端滑上传送带，则物体一定先做加速运动，再做匀速运动     D．物体从右端滑上到左端所需的时间可能等于物体从左端滑上到右端的时间