Although that answer is correct, I can say it better.
The correct answer is A. always requires a prescription.
Explaination: Take note that the question was all of the following EXCEPT!
Supplements can be sold over the counter so B is not correct.
Supplements do not need to be regulated by the FDA even if the supplements even if they don't show evidence of effectiveness so C and D are also incorrect, so the right answer can only be A because a prescription is not required to get the supplement.
Thank you for your time.