Which type of compound does the sentence contain?

gina and sydney only have three days left of their vacation.
a) compound subject
b) compound object
c) compound interjection
d) compound verb

The correct answer is A. compound subject.

Compound means complex, made up of several parts. In the example above, the subject of the sentence is Gina and Sydney. As you can see, the subject contains two parts - Gina and Sydney, brought together by the conjunction and. Since there are more than one part of a subject, it means that it is compound.

There are no objects or interjections in this sentence; the verb is simple (have) so it cannot be compound.