What must agree in number within a sentence?

• A. The subject and verb must agree in number; a singular subject requires a singular verb, and a plural subject requires a plural verb.
• B. The subject and object must agree in number.
• C. The verb tense determines number agreement.
• D. Only subjects determine verb agreement.

Answer: (A)

The main rule being tested is number agreement between the subject and the verb. The verb must match the subject in number: a singular subject takes a singular verb, and a plural subject takes a plural verb. For example, The dog barks uses a singular verb, while The dogs bark uses a plural verb. Objects do not determine the verb form, so subject–object number agreement isn’t required. Verb tense describes when something happens, but doesn’t set whether the verb is singular or plural. There are exceptions with collective nouns or when the subject is a compound or represents individuals within a group, which can shift whether the verb is treated as singular or plural, but the guiding idea remains: the subject determines the verb’s number.