Final answer:
Gatekeeping is the answer. Under gatekeeping, a primary care physician becomes the portal of entry to the health care delivery system.
Step-by-step explanation:
The answer to the question is gatekeeping. Under gatekeeping, a primary care physician serves as the portal of entry to the health care delivery system. This means that patients must first visit their primary care physician to obtain a referral before seeing a specialist or accessing certain healthcare services. Gatekeeping helps to manage and coordinate the patient's healthcare and control costs by ensuring that patients receive appropriate and necessary care.