VII. Mark the letter A, B, C, or D to indicate the correct response to each of the following exchanges.

1. Nam: What is the biggest environmental problem facing our country?      -   Lan: ___________

A. Too much toxic sewage is dumped at sea.  

B. All countries face environmental problems.

C. No one can help protect the environment.

D. Our country is facing the biggest environmental problem.

One / friends / always/ help/ homework because/ intelligent.