The correct answer is A. John sells bonds more quickly than Carol
Explanation:
In grammar, an adverb refers to a type of words used to describe or modify actions, some of these words end in "-ly" such as the words peacefully, rarely, quietly or quickly; however, words like always, already, today or very also work as adverbs, because they usually tell in which mode, way, time, place or frequency does an action take place. Additionally to this, when adverbs are used for comparison, if the adverb has only one syllable the comparative is formed by adding "-er", but in the case or two or more syllables the adverb is not changed but the word "more" is added to it. Considering this, in the case of the adverb "quickly" which has two syllables the correct comparative form is "more quickly" and therefore the sentence that contains the correct form of the adverb is "John sells bonds more quickly than Carol".
