The Client Is Enrolled in a Clinical Drug Trial, and Is

The client is enrolled in a clinical drug trial, and is told that he might receive a placebo drug as part of a control group.The client asks the nurse what a placebo is.The nurse's best response is:

A) "A placebo is a drug that has been tested before."
B) "A placebo is an over-the-counter drug."
C) "A placebo is an inert substance."
D) "A placebo is similar drug that is safe."