Answer:
A. Expertise
Step-by-step explanation:
Advertising is the use of paid messages to communicate with the end-users of a product or service. Advertising seeks to create or increase the demand for goods and services. It informs consumers of the features and benefits of using a particular product, thereby enticing them to buy.
Sometimes marketers get experts or professionals to endorse a product or a service as a way of advertising. When an expert or a satisfied customer vouch for the effectiveness of a product, customers tend to get convinced. The advert achieves its purpose of increasing sales.