In Efforts to Reform Negative Advertising

In efforts to reform negative advertising,

A) some newspapers and websites have taken to doing "spot checks" on candidates' claims and publishing the truth in the event of false claims.
B) some major newspapers were intimidated when candidates took them to court.
C) political parties have created "Fair Campaign Practices" panels that must approve all campaign ads.
D) the Democratic Party has brought court action against Republican candidates in forty states for defamation of the character of their candidates.