Registration in Professor McNick's Classes Reaches Maximum Enrollment Quickly

Multiple Choice

Registration in Professor McNick's classes reaches maximum enrollment quickly. Students register immediately online just to insure their seat in her class. One student summed it up: "Everyone's heard she is the best teacher on campus." Professor McNick's classes benefit from:

A) viral publicity.
B) positive public relations.
C) free advertising.
D) word-of-mouth promotion.