Which solution should a consultant recommend to prevent this scenario from happening in the future?

A customer-submitted case is routed to a service desk agent at Universal Containers. After the agent responds to the case, the agent realizes the customer is not eligible for support.

Which solution should a consultant recommend to prevent this scenario from happening in the future?
A . Add the entitlement related list to account page layouts.
B . Add the entitlement lookup field to case page layouts.
C . Add a Validation Rule that ensures each Case has an entitlement.
D . Add a Validation Rule that ensures each Account has an entitlement.

Answer: A