Mark the letter A, B, C, or D to indicate the correct response to each of the following exchanges. Two friends Nam and Lan are talking about the topic of global warming.
Lan: How can ordinary people help protect the environment? - Nam: ____
A. What can ordinary people do to help the environment?
B. Environment really needs our help.
C. We may use environmentally-friendly products.
D. Both governments and individuals are to blame on.