Choose the correct answer A, B, C, or D.

1. You should decide _______ to move to the new house.

A. while                     B. when

C. where                   D. who

2. Do you know _______ to sort rubbish?

A. who                     B. which

C. how                     D. what

3. She didn't tell me _______ to meet, in the library or in the lab.

A. how                    B. when

C. what                   D. where

4. Could you tell me _______ to do in this situation?

A. what                 B. when

C. where              D. who

5. I wonder _______ to ask for advice, my teacher or my parents.

A. where               B. when

C. who                  D. what