Case advocacy is best defined as:

Case advocacy is best understood as an intervention specifically focused on representing the interests of an individual or family in order to secure access to necessary services. This type of advocacy typically involves working directly with service providers or systems to ensure that clients receive the specific help they need, such as healthcare, housing, or social services. It is characterized by a personalized approach, where the advocate engages with the nuances of an individual’s situation, making a compelling case for the services or support required.

The other options describe different forms of advocacy that do not align with the essence of case advocacy. The model combining public education and delivery of a concrete service emphasizes a broader approach that includes educating the public and directly providing services rather than solely advocating for an individual’s needs. Influencing policy by making a case before the public reflects a form of systemic advocacy focused on legislative or social change, rather than the personal focus of case advocacy. Lastly, intervening on behalf of multiple groups carries a community or population-wide perspective, aiming to address collective issues rather than the specific needs of an individual or family. Each of these distinctions helps clarify why the focus of option A is the most accurate representation of what case advocacy entails.