With Regard to Voting Patterns, Which Statement Is Best Supported

With regard to voting patterns, which statement is best supported by the existing empirical data?

A) Voters support challengers over incumbents in primary elections.
B) Voters tend to evaluate candidates based on their individual economic circumstances.
C) Voters gain a great deal of information from political advertising and use it as the primary basis of their vote.
D) Voters tend to judge a presidential candidate on the basis of prevailing economic trends.