A Patient Wants to Know Why a Cheaper Version of a Drug

A patient wants to know why a cheaper version of a drug cannot be used when the primary care NP writes a prescription for a specific brand name of the drug and writes,"Dispense as Written." The NP should explain that a different brand of this drug:

A) may cause different adverse effects.
B) does not necessarily have the same therapeutic effect.
C) is likely to be less safe than the brand specified in the prescription.
D) may vary in the amount of drug that reaches the site of action in the body.