Merry . . . . . two husbands.

Let's break down why "Option A: has" is the correct answer:
- Option A: "has" is the singular form of the verb "to have." It agrees in number with the singular subject "Merry." So, "Merry has two husbands" is grammatically correct.

The other options are incorrect because:
- Option B: "have" is the plural form of the verb "to have." It does not agree in number with the singular subject "Merry."
- Option C: "is" is the singular form of the verb "to be," but it doesn't fit in the context of the sentence. "Merry is two husbands" would not make sense.
- Option D: "are" is the plural form of the verb "to be" and is also not suitable for this sentence. "Merry are two husbands" is grammatically incorrect.

In summary, the correct answer is "Option A: has" because it correctly matches the singular subject "Merry" with the singular verb "has," resulting in the grammatically correct sentence "Merry has two husbands."