Which of the options, (1), (2), (3), given below the sentence should replace the phrase printed in bold type and underlined to make the sentence grammatically correct? If the sentence is correct as it is, mark (D) as the answer.
If I would have realised the nature of the job earlier, I would not have accepted it.

Options

A. If I have had
B. In case I would have
C. Had I realised
D. No correction required

Answer

C