Which One of the Following Individuals Is Exhibiting Conventional (Stage

Which one of the following individuals is exhibiting conventional (stage 3 or 4) reasoning as Kohlberg defined it?

A) Adam does what the teacher says because he knows he'll be punished if he doesn't.
B) Barbara obeys the teacher because doing so increases the likelihood of good grades.
C) Clara obeys the teacher because she understands rules are useful,but would disobey them if she believed that they violated her own ethical principles.
D) Don obeys the teacher because school rules say he must obey her,and it is his duty to obey school rules.