Though they had a meeting yesterday there is still much that remains.A. to solveB. to be

问题补充：

Though they had a meeting yesterday, there is still much that remains.

A. to solve

B. to be solved

C. solving

D. solved

答案：

A. to solve

(答案→)B. to be solved

C. solving

D. solved

解析：remain后面要求不定式做表语，根据题意这里要被动形式，所以选B。