boys/ clever/ see/ solution/ problem/ so quick...

Câu hỏi: boys/ clever/ see/ solution/ problem/ so quickly//

A. The 'boys were clever to see the solution to the problem so quickly.

B. Boys are clever to see the solution of problem so quickly.

C. The boys are clever at seeing the solution to the problem so quickly.

D. The boys were clever to see the solution of the problem so quickly.