John doesn't know very much about electronic equipment, but he wanted to get his girlfriend a tablet for her birthday. his roommate, hank, knows all about these types of products and made a recommendation to john. for this product category, hank is known as a(n)

Opinion leader or influencer

Explanation:

opinion leaders are those people who are mostly expert in a particular industry Information and their views or opinions are well known and commonly trusted. For this reason people usually count on their opinions and can use their influence in decision making process.

The Role of Opinion Leaders in Marketing

Opinion leaders have obtained an authority or power in a particular market in such that they are very good at impacting the audience on what is trending and hence impact the consumer or customers behavior. Some do this professionally and some have established the confidence within their community online or in their physcal vicinity.

Their opinions is used to validate the product just like Hank is doing for John validating his decision by giving him all the necessary information that he needs and making recommendations.