Read the sentence below to find out whether there is any grammatical error in it. The error, if any, will be in one part of the sentence. Choose the option with that part as your answer. If there is no error, choose 'D' as your answer. (Ignore the errors of punctuation, if any).

The reason why he was rejected was because he was too young.

A.

The reason why

B.

he was rejected

C.

was because he was too young.

D.

No error.

Correct answer is C

was that he was too young