The correct answer is B. Influencer
Step-by-step explanation:
In the purchasing process, an influencer refers to an individual who influences or affects the purchasing process; this includes the type of products other people buy, the reasons to buy them, and the frequency these are bought. Due to this, influencers can make other people pay for certain services or products or abstain from doing this.
In the case presented, Ruth acts as an influencer because through her actions she convinces her family they need to buy a refrigerator, which means she affects the purchasing process. Also, as an influencer, she is the one that chooses the type of product and she informs the buyers (her parents) about the reasons for buying this.