Final answer:
Medication administration is a dependent nursing intervention, requiring a physician's order. The oral route is a convenient method for home administration of an antimicrobial for systemic infections.
Step-by-step explanation:
Dependent interventions are those actions that require an order from a physician or another healthcare professional. In the context of administering medication, a nurse must follow the prescribed orders regarding which medication to give, as well as the dosage, route, and timing of administration. Regarding the appropriate and convenient route for home administration of an antimicrobial to treat a systemic infection, the oral route (Option A) would be suitable. Oral medication is generally the preferred method for home use due to its ease of administration and the fact that it does not require special skills or equipment that other methods, such as intravenous or parenteral administration, may necessitate.