第24题: [单项选择]The electric catfish has a different electric system in that A. current moves from the head to the tail. B. current moves from the tail to the head. C. current moves from the left to the right. D. current moves from the right to the left. 参考答案:B 答案解析:[解析]由文章倒数第二段第一句“The electric catfish of the Nile and of other African fresh waters has a different s