Which choice exemplifies a medical assistant's main responsibility?

The main responsibility of a medical assistant often includes direct patient care, and obtaining vital signs is a foundational duty that aligns with this role. Gathering vital signs—such as blood pressure, pulse, temperature, and respiratory rate—helps healthcare providers assess a patient's health status and make informed decisions regarding their care. This task is typically one of the initial steps in the patient visit process, which highlights the medical assistant's role in facilitating patient care and maintaining efficient workflows in a clinical setting.

While other choices represent important duties within a medical office, they do not directly pertain to the primary function of a medical assistant in patient interactions. Speaking with insurance companies can be performed by various staff members, the safety of the working environment is a broader responsibility that may extend beyond the medical assistant's scope, and assigning billing codes is typically part of the administrative or coding specialist's role. Therefore, obtaining vital signs stands out as a quintessential task that captures the essence of the medical assistant’s involvement in patient care.