Which of the Following Procedures Is an Example of the Use

Multiple Choice

Which of the following procedures is an example of the use of a placebo?

A) In a test of the effects of a drug on memory,a participant is led to believe that a harmless pill actually contains an active drug.
B) A participant in an experiment is led to believe that a pill,which actually contains an active drug,is harmless.
C) Participants in an experiment are not told which treatment condition is in effect.
D) Neither the participants nor the experimenter knows which treatment condition is in effect.