One Reason That Public Policy Often Differs from Public Opinion

 One reason that public policy often differs from public opinion is that 

A)  the U.S. Constitution places many checks on the influence of public opinion. 
B)  public opinion polling tends to express the opinions of a political elite. 
C)  public opinion is easy to gauge, whereas the effectiveness of public policy is not. 
D)  public opinion tends to change much more slowly than public policy. 
E)  public opinion is rarely informed at the beginning of the policymaking process.