Which statements about the National Health and Social Life Survey conducted by researchers at the ...

Which statements about the National Health and Social Life Survey conducted by researchers at the University of Chicago is false?
 
  a. The researchers attempted to obtain a representative sample of the U.S. population.
  b. The results indicate that people in committed, one-partner relationships tend to have the most sex.
  c. The survey contained controversial questions regarding pornography, pedophilia, and sexual fetishes.
  d. About a third of the participants reported having sex only a few times, or not at all, in the preceding year.