When taking medication, you should always
a.
tell your doctor about other medication you may be taking
b.
stop immediately after the symptoms disappear
c.
take as much as needed to feel better
d.
refer to online resources for dosage recommendations

The answer A is a seeing as B you would have to not even take the medicine C you could potentially overdose and D online resources aren't really the best option for answers ironic I know

A. tell your doctor about other medication you may be taking.

Explanation:

When your doctor is going to prescribe medication for you, you have the obligation to tell him if you are taking other medications at the moment, or some allergic reactions you may have to some components.

If you don't tell your doctor about other medication you may be taking, instead of healing you could have a worse health state.

Therefore, the right answer is A.

Is there any choices ?

This needs more info