In which of the following research settings would you not need to get approval from an institutional ...

In which of the following research settings would you not need to get approval from an institutional review board?
 
  a. research involving interviews of undercover police officers
  b. research involving surveys given to students in all sociology classes at your university when students' names are not recorded
  c. interviews with faculty in your major about the most pressing issues that they see with respect to their students
  d. research involving observations in a county clinic regarding the prescription dosages for adult patients