Answer:
a) is the only true answer
Explanation:
Over the counter means you don't need a prescription to get the medication. This can include Tylenol, Advil, etc.
Think of it this way, it is over the counter, you can reach and take it without needing anyones permission.
You still do need to read what is written as instructions, of course! That is for all medications, over the counter or not.
