Correct Answer:
B. is
The correct answer is B: is. This question tests your knowledge of subject-verb agreement, particularly with nouns that appear plural but are grammatically singular. Words like "mathematics," "physics," "news," "economics," "mumps," and "measles" end in "-s" but refer to a single field of study, a single piece of information, or a single disease. Therefore, they require a singular verb.
Here's why "is" is correct:
- Singular Concept: "Mathematics" refers to a single academic discipline or field of study, not multiple individual subjects.
- Grammatical Rule: Nouns that denote a single entity, even if they have a plural form, take a singular verb.
If the sentence were referring to mathematical calculations or problems, it might use a plural verb, but "mathematics" as a subject is always singular. Options A ("are"), C ("were"), and D ("have") are all plural verb forms and are incorrect in this context because "mathematics" functions as a singular subject.