What level of health care is delivered by a member of the health care system responsible for the majority of an individual's health care needs?

Primary care is the correct answer because it represents the level of health care that is typically delivered by healthcare providers who serve as the first point of contact for individuals seeking health services. These providers, which include general practitioners, family physicians, and pediatricians, are trained to handle a wide range of health issues and are responsible for managing the majority of an individual’s health care needs. They focus on preventive care, health education, and the treatment of common illnesses and conditions, making them crucial in maintaining overall community health.

In contrast, secondary care usually refers to specialized services that require a referral from a primary care provider, often involving specialists like cardiologists or orthopedic surgeons. Tertiary care involves even more specialized and advanced levels of care, typically provided in specialized facilities such as hospitals with advanced medical equipment for complex conditions, while quaternary care refers to even more specialized care, often experimental or highly specialized interventions not widely available. These levels of care support but do not encompass the comprehensive, first-line approach that primary care offers.