The following question has a sentence with three underlined parts labelled (a), (b) and (c). Read each sentence to find out whether there is an error in any underlined part and indicate your response against the corresponding letter i.e., (a) or (b) or (c). If you find no error, your response should be indicated as (d).No one knows (a) why he did it, (b) or who was behind his doing it. (c) No error. (d)

• A. A
• B. B
• C. C
• D. D