Sam coins since he was eleven years old and now he has hundreds of them.A. collectedB. h

问题补充：

Sam coins since he was eleven years old, and now he has hundreds of them.

A. collected

B. had collected

C. has been collecting

D. had been collecting

答案：

A. collected

B. had collected

(答案→)C. has been collecting

D. had been collecting

解析：考查时态。句意“萨姆自从11岁就开始收集硬币了，现在他有几百个了。”表示动作发生在过去，一直持续到现在，有可能继续持续下去。用现在完成进行时。故选C。