Ten minutes had been made full of the problem.A. using; studyingB. use; to studyC. to us

问题补充：

Ten minutes had been made full of the problem.

A. using; studying

B. use; to study

C. to use; to study

D. use; studying

答案：

A. using; studying

(答案→)B. use; to study

C. to use; to study

D. use; studying

解析：句意：十分钟的时间正在被充分利用来研究这个问题。make full use of 充分利用，用的是被动语态，目的是为了研究这个问题，to表示了为了什么目的

选B。