—He looks unhappy.

—Yes,but he can’t say what it is_______is bothering him.

A.as               B.that             C.what           D.which

---- He looks unhappy.

   ---- Yes, but he can’t say what it is _____ is bothering him.

  A. that  B. who  C. what  D. which

---He looks unhappy.
---Yes,but he can’t say what it is______is bothering him.

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