Which of the Following Is True of Negative Advertisements

Which of the following is true of negative advertisements? 

A)  They always bring about a higher voter turnout in elections. 
B)  They cannot inform voters about important issues like positive advertisements. 
C)  They are more likely than positive advertisements to grab viewers' attention. 
D)  They are believed to be a force for bad as they dull public debate. 
E)  They are less likely than positive advertisements to get free media coverage.