Question

The teacher set such a difficult problem ________none of us could solve.

1. A.
   that
2. B.
   so that
3. C.
   which
4. D.
   as

Answer 1

D
定语从句考查题。先行词problem有such修饰，关系词只能用as不能用that或 which，as在从句中做solve的宾语。