Answer:
The correct answer is A, Adoption.
Step-by-step explanation:
Product Adoption is the process of hearing about the product and buying it. In Adoption Process, there are many steps involved like Awareness, Interest, Evaluation, Trial and Adoption. A person goes through these stages before buying a product.
In this case, Kevin's friend see his new phone, took interest, evaluate its features, try it with him and then decides to buy it. So they are involved in the adoption process of the product.