Concept:Commercial occupations cover all activities that support the buying, selling, and distribution of goods and services, including trade and its auxiliary services such as insurance and banking.
Explanation:A bricklayer is involved in construction, which is a form of industrial or productive occupation.
An engineer also belongs to the industrial sector because their work focuses on designing and building structures or machinery.
A barber gives a direct personal service and is therefore not engaged in a commercial occupation.
An insurance broker, however, acts as a helper or intermediary in the selling of insurance services.
Insurance is an aid to trade, meaning it facilitates the smooth conduct of business activities.
Since the broker supports trade and exchange, this role falls under commercial occupation.
Answer:C. an insurance broker