A Scientist Is Designing a Clinical Trial to Test the Effect

Multiple Choice

A scientist is designing a clinical trial to test the effect of online chat counseling with migraine sufferers as a supplementary treatment in combating their migraines. Migraine sufferers will have access to counselors via online chat software; the scientist plans to see whether their migraine pain has been reduced after six weeks.
The subjects would obviously know whether or not they were given access to the counseling. What experimental technique does this eliminate?

A) informed consent
B) randomization
C) blinding
D) confounding