What is the main function of the Card Authorization System (CAS) used by American Express?

The primary function of the Card Authorization System (CAS) utilized by American Express is to protect against fraud loss and credit abuse. This system is integral to the authorization process for transactions made with American Express cards. It evaluates potential risks associated with each transaction and assesses various factors, such as transaction patterns and cardholder behavior, to determine whether to approve or decline a transaction.

By prioritizing the protection against fraudulent activities and ensuring proper use of credit, CAS helps safeguard both consumers and the issuer from the financial repercussions that can arise from unauthorized transactions. The system's sophisticated algorithms and real-time analysis contribute significantly to maintaining trust in the payment process for all involved parties.

In contrast, other options cover functionalities that are not the central purpose of CAS. While it is true that managing cardholder rewards or handling inquiries are important aspects of a credit card company's offerings, these tasks do not align with the core role of the Card Authorization System. Therefore, the accurate selection is focused on fraud prevention and credit protection, underscoring the importance of secure transaction processing in the evolving landscape of payments.