She said, "Madam, I have done homework."

A She said respectfully that she had been done homework.

B She said respectfully that she has done homework.

C She said respectfully that she had done homework.

D She said respectfully to her teacher that she had done homework.

Correct Answer: Option C

Note: while changing it to indirect speech, remove "Sir/Madam" with "respectfully" as we did in this question.