In a Study of Interpersonal Attraction, Subjects Watched a Videotape

In a study of interpersonal attraction, subjects watched a videotape featuring a person who was (1) either competent or incompetent, and (2) either did or did not spill coffee on himself (i.e., "blundered") . After watching the tape, all subjects indicated how much they liked the person in the film on a seven-point scale. Consider the following outcome:
This outcome shows

A) a main effect for competence only.
B) a main effect for blunder only.
C) main effects for both competence and blunder.
D) an interaction between competence and blunder.