Concept:After the auxiliary verb "did," we always use the base form (first form) of the main verb.
Explanation:The sentence uses "did" to form the past tense question.
"Did" is already past tense, so the main verb must stay in its root form.
Among the options, "need" is the base form.
"Needed" is past tense and not used after "did."
"Knead" and "kneed" are different verbs and do not fit the meaning.
Thus, the correct choice is "need."
Answer:C. need