Final answer:
A. Place the medication between the lower teeth and cheek. A buccal medication should be placed between the lower teeth and the cheek.
Step-by-step explanation:
A buccal medication refers to a type of medication that is placed between the cheek and the gum. The medical assistant should instruct the patient to place the medication between the lower teeth and the cheek, so option A is the correct answer. This allows the medication to be absorbed through the mucous membranes in the mouth and enter the bloodstream directly, bypassing the digestive system. An example of a buccal medication is a sublingual tablet, which is placed under the tongue, as mentioned in option C.