Final answer:
The service-mix index (SM) is used in the Inpatient clinical setting.
Step-by-step explanation:
The service-mix index (SM) is used in the Inpatient clinical setting. It is a measure of the complexity of services provided in a hospital or healthcare facility. The SM index takes into account factors such as the range of services offered, the number of different types of patients treated, and the intensity of care required.
For example, an inpatient setting may have a higher SM index if it offers specialized services like cardiothoracic surgery and treats a diverse range of patients with different medical conditions.
Therefore, the correct answer is: a) Inpatient.