Answer:
Quickly
Step-by-step explanation:
An adverb is every word capable of characterizing the verbal process, indicating the circumstances in which this process develops. Thus, the basic function of adverbs is to relate to the verbs of the language by characterizing the processes expressed by them.
"Quickly" is an adverb and, in this case, indicates the way it goes. "Fast" is an adjective, but can also be used as an adverb, with the same sense of urgency.