Final answer:
An outpatient is a person treated in all of the above settings, including the hospital observation unit, ambulatory surgery center, and physician's office.
Step-by-step explanation:
An outpatient is a person treated in all of the above settings, which include the hospital observation unit, ambulatory surgery center, and physician's office. An outpatient is a patient who receives medical treatment without being admitted to a hospital or staying overnight. They typically visit these settings for diagnostic testing, minor surgeries, or follow-up appointments.