What does an adverb modify?

An adverb primarily modifies a verb, which is why option B is accurate. Adverbs provide context by describing how, when, where, or to what extent an action occurs, thus enhancing the meaning of the verb. For instance, in the sentence "She runs quickly," the adverb "quickly" gives more information about how she runs.

While it is true that adverbs can also modify adjectives and other adverbs, the focal point of this question is on what adverbs typically modify, which is the verb. Therefore, while adverbs have a broader application in language, the direct and primary modification relates to verbs, making option B the most fitting choice.