Research Suggests That Negative Campaigning in Politics May Be MOST

Research suggests that negative campaigning in politics may be MOST effective as a strategy ____.

A) for a candidate who is far behind in the polls and willing to try anything to get ahead
B) as a retaliation measure, for a candidate who has already been attacked by his or her opponent
C) for candidates who already have the upper hand in the polls
D) for candidates who are relatively well-known (as opposed to those who are less well-known)