Interpret the Impact of Negative Ads on the Outcome of a Campaign

Interpret the impact of negative ads on the outcome of a campaign, as evidenced by the 2012 U.S.presidential election.

A) Negative ads are effective in swaying voters unidentified with a political party.
B) Negative ads almost always assure a win for the party that runs them.
C) Voters tend to tune them out, and thus, they have little effect.
D) Campaigns profit from negative ads by attacking their opponent's weak points.