Directions: The following sentence has four parts marked (A), (B), (C), (D) and (E). One of the parts may contain an error and if so, identify the part that contains the error and choose the letter corresponding to that part from the given options. If the sentence does not contain any error, mark (E) as your answer.

I am thankful to (A)/ my elder brother (B)/ who did all my homework (C)/ upon my behalf. (D)/ No error (E)