A registered nurse that has additional training and can provide some basic primary care is a(n):

A nurse practitioner (NP) is a registered nurse who has completed additional training and education, typically at the master's or doctoral level, allowing them to provide a range of primary and specialty care services. This includes conducting physical exams, diagnosing and treating medical conditions, interpreting diagnostic tests, and managing patient care. NPs are also authorized to prescribe medications in many states, further extending their role in patient care.

While other roles like licensed practical nurses (LPNs) and registered nurses (RNs) are essential in healthcare, they do not have the same level of training or scope of practice as nurse practitioners. LPNs generally provide basic nursing care under the supervision of RNs or physicians and have more limited responsibilities. RNs, while highly trained, do not typically provide the same level of independent primary care services as NPs. A medical social worker (MSW) focuses on the psychosocial aspects of care and does not fall under nursing practice.

Thus, the designation of a nurse practitioner accurately reflects a healthcare professional who has advanced skills to deliver primary care, making it the correct choice.