阅读短文，根据短文内容，从各题所给的四个选项中选择一个最佳选项。

    There is an elephant and a monkey. They're friends, but one day they want to know who is stronger（更壮）. One of them says, "Who can get apples over there, who is stronger."

    There's a river over there. Monkey says, "I can't swim." Elephant says, "I can swim. Please sit on my back." They go across the river. The apple trees are very high. The elephant can't reach（够着）the apples. The monkey climbs（爬）up the tree and gets many apples.

    Now they know they should help each other.