Which statement about subject-verb agreement is correct?

• A. Subject-verb agreement is optional in formal writing.
• B. The subject and verb must agree in number; a singular subject requires a singular verb.
• C. Verbs do not need to agree with subjects.
• D. Only verbs determine subject-verb agreement.

Answer: (B)

The main point tested is number agreement between the subject and the verb. In standard English, the form of the verb must match the subject in number: a singular subject takes a singular verb, while a plural subject takes a plural verb. This keeps sentences clear and grammatically correct. For example, "The dog barks" uses a singular verb because the subject dog is singular, whereas "The dogs bark" uses a plural verb because the subject dogs is plural. This rule underpins formal writing, where consistent agreement signals accuracy and helps avoid confusion.

The statement that agreement is optional is not correct; it would lead to awkward, unclear sentences. The idea that verbs do not need to agree with subjects is also incorrect, since the link between the subject’s number and the verb’s form is exactly what governs the construction. The notion that only verbs determine subject-verb agreement misses the fact that the subject’s number drives the verb form.