Answer:
Option A (Both the adjuster and the student we potential customers because in their own way, they both benefit from the product).
Explanation:
Both the adjuster and the student were potential customers as they were both buying the smartphone for either personal or official use. The adjuster sees the smartphone as a product or tool that could be used to make work efficient. The student sees the product as a luxury. Either way, they are buying the smartphone and as such, they are very important to the producers of the smartphone because the product is useful to both of them.