Which sentence uses a verb that agrees with its compound subject?
a. a saw and a drill is important for a carpenter's work.
b. those suitcases and this trunk have traveled many miles.
c. now either freezers or a refrigerator keep food fresh.
d. cathy and beth takes the bus to ballet lessons.

The sentence that uses a verb that agrees with its compound subject is: Those suitcases and this trunk have traveled many miles. The correct answer is option B. The compound subject is "those suitcases and this trunk" which is a compound and a plural subject. Therefore, the verb that should be used is also plural, which is "have".