Correct Answer:
A. has done
Subject-verb agreement dictates that a verb must agree in number with its subject. When "neither of" is used, the subject is considered singular, even if the noun following "of" is plural.
- The correct answer, has done, is accurate. "Neither" acts as a singular pronoun, meaning "not one." Therefore, it requires a singular verb form. "Has done" is the singular present perfect tense, correctly agreeing with "neither."
- Have done is plural and would be incorrect with the singular subject "neither."
- Is doing is singular but implies an ongoing action, which might not fit the context of completed homework as well as "has done."
- Were doing is plural and past continuous, incorrect for both number agreement and tense in this context.
Correct subject-verb agreement is fundamental for grammatical accuracy.