Christine Conducted a Study Looking at How Images of Thin

Christine conducted a study looking at how images of thin female bodies influenced participants' views of their own bodies. She told participants as much as she could before the study began but had to use some deception. Participants were told that their job was to look at a series of images of women and rate the appeal of the clothing being worn. Afterwards she had participants fill out questionnaires, including a measure of body dissatisfaction. Once participants filled out the questionnaires, she thanked them and sent them on their way. What ethical guideline did Christine fail to follow?

A) She did not use a double-blind study.
B) She did not tell her participants the exact reason for her study before it began.
C) She did not follow the principle of autonomy.
D) She did not debrief her participants.