Answer:
a. c. and d.
Explanation:
Credit cards are extremely commonly used because of its ease of use and because it gives both sellers and buyers many benefits. For sellers they allow customers to use credit cards because they do not have to decide who gets credit, seller receives cash sooner than if credit is granted directly to the customers, and may even allow the seller to increase sales volume. This in general gives the seller a new payment option that is widely used which in term brings in more customers as they are able to purchase the products with money they do not currently have.