Read the following sentence.

Vanessa was always more gregarious than Mary; Mary liked staying home while Vanessa loved parties and social events.

Given how it is used in the sentence, what is the most likely meaning of gregarious?
A.
marked by a liking for companionship

B.
defined by a liking for solidarity

C.
loud and obnoxious

D.
outspoken and forward in one's behavior

A. marked by a liking for companionship