题目

阅读理解 Elephants don't forget-at least, female(雌性的) elephants don't. Elephant families are matriarchal. And the social knowledge gained by the oldest females is the key to a family group's survival (生存), according to a study published in April by Karen McComb, a biologist at Sussex University in England. Elephants announce their presence by making a deep, long sound, a practice referred to as contact calling(联络呼叫). An unfamiliar call may mean that an elephant from outside the family group is nearby. A stranger can cause trouble. Interrupting feeding or disturbing the yo一点电荷仅受电场力作用，由A点无初速释放，先后经过电场中的B点和C点。点电荷在A、B、C三点的电势能分别用EA、EB、EC表示，则EA、EB和EC间的关系可能是[　 　]A．EA＞EB＞EC       B．EA＜EB＜EC    C．EA＜EC＜EB      D．EA＞EC＞EB