—I forgot my mother's birthday!— Better keep it in mind next year.A. I'm afraid so.B. So w

问题补充：

—I forgot my mothers birthday!

— Better keep it in mind next year.

A. Im afraid so.

B. So what?

C. You did?

D. No wonder.

答案：

A. Im afraid so.

B. So what?

(答案→)C. You did?

D. No wonder.

解析：C 考察交际英语。句义：—我忘记妈妈的生日了！—你忘记了？最好明年记住吧！A恐怕如此；B那又怎么样？D不足为奇；C项中的did指代上文中的forot，意为你忘记了？表示惊讶。故C正确。