The sentence refers to a past action at a specific point in time, which requires the past simple tense.
In negative sentences using the past simple, the auxiliary verb "did" is used, followed by the base form of the main verb.
The correct sentence should be:
"He didn't know the answer to the question."
Thus, the correct answer is (B) "didn't know."
List-I (Sentence) | List-II (Idiom) |
---|---|
(A) The officer tried to ______ his ideas with his superior by constantly praising. | (I) put your nose to the grindstone |
(B) She realised that she was in the wrong and promised to ______. | (II) read between the lines |
(C) You will do well at academics if you ______. | (III) turn over a new leaf |
(D) A cryptic writing-style forces you to ______ the true meaning of the piece. | (IV) curry favours |