为自己加油

Choose the closest paraphrased version for the sentence or italicized part.

He could think of no answer but the truth. （）​​​​

A.
He had to tell the real fact because he could not find other answers.
B.
He had to tell the truth if he was asked.
C.
He had to tell the truth if he could not answer.
D.
He answered but that was not the real fact.