The correct answer is:

✅ D. Enable schedules on product object

✅ Explanation:
Since Universal Publications sells subscriptions that can be one-time or recurring (weekly, monthly, quarterly), they need to track payment amounts over time. Salesforce offers a feature called Product Schedules, which can handle this exact scenario.

✅ D. Enable schedules on product object
✔ Correct – This allows you to define revenue schedules (e.g., monthly payments) or quantity schedules (e.g., deliveries). When enabled, Salesforce can automatically distribute the opportunity amount over the payment intervals for accurate tracking and reporting.

Actually the right answer is D according to the above link: Create default revenue and quantity schedules for products that are delivered or paid for over time. Let users create schedules for individual products on opportunities. In Lightning Experience, enable customizable product schedules to tailor schedule layouts with custom fields and buttons and to apply validation rules and Apex triggers.

Answer: C
https://help.salesforce.com/s/articleView?id=sf.products_schedules_def.htm&type=5

You don't need to know what magazines the subscriber has, so it is not the A.