Identify the segment in the sentence which contains the grammatical error.
He / didn’t knew / the answer / to the question.

Correct option is A

Option (a) didn't knew contains the grammatical error.
Explanation:
· When using did (past tense auxiliary), the main verb must be in base form (V1).
· “knew” is V2, so it should be corrected to “know.”
Grammatical Rule Used:
Do/does/did + base form of the verb (V1)
Incorrect: didn’t knew → didn’t know
Correct He didn’t know the answer to the question.