Son: Father, you promised that if I did well in the exam you would buy me a new bike.
Father: ________ I will buy it tomorrow.

Son: Father, you promised that if I did well in the exam you would buy me a new bike.
Father: ________ I will buy it tomorrow.

A. So did I.

B. Really?

C. So I did.

D. You should keep your promise.

正确答案是C