—Are you sure Mike will help us if we are in trouble? — . He is a reliable friend.A. It do

问题补充：

—Are you sure Mike will help us if we are in trouble?

— . He is a reliable friend.

A. It doesn’t matter

B. Don’t take it to heart

C. You can count on it

D. No problem

答案：

A. It doesn’t matter

B. Don’t take it to heart

(答案→)C. You can count on it

D. No problem

解析：考查交际用语。A. 没关系 B. 别忘心里去

C. 你尽管相信好了 D.没问题

句意：你确信如果我们遇到麻烦麦克 会帮助我们？结合下文他是我最信赖的朋友，可知选C最符合语境。