A friend of yours was asked to be a research participant for a study investigating the effect of a pain reliever on muscle tears

In order to test the effectiveness of the drug, your friend will need to engage in physical activity that results in small tears in the muscles of the forearm. You caution that all studies involving human subjects must include:

a. freedom from risks.
b. monetary benefits for participants.
c. informed consent.
d. parental consent even if over the age of 18 years.

Answer: C