How can the customer take advantage of volume discounts with minimal impact to the AWS resources?

A customer is using multiple AWS accounts with separate billing.

How can the customer take advantage of volume discounts with minimal impact to the AWS resources?
A . Create one global AWS acount and move all AWS resources to tha account.
B . Sign up for three years of Reserved Instance pricing up front.
C . Use the consolidated billing feature from AWS Organizations.
D . Sign up for the AWS Enterprise support plan to get volume discounts.

Answer: C

Explanation:

Reference: https://aws.amazon.com/answers/account-management/aws-multi-account-billing-strategy/