A Frenchman who lost his arms and legs successfully swam across the Channel, a challenge he for two years.
A. has been preparing
B. had been preparing
C. has prepared
D. prepares
网友回答
A. has been preparing
(答案→)B. had been preparing
C. has prepared
D. prepares
解析：这题考查现在完成进行时的用法：现在完成进行时表示过去到现在一直在进行的动作，句意是：一个失去膀子和腿的法国人成功的游过了海峡，这是他准备了两年的挑战。选B。