Which of the following is NOT a type of payments processor?

The answer identifies "Cardholder manager" as a term that does not categorize as a type of payments processor within the payment processing ecosystem.

Payments processors are crucial intermediaries in the transaction flow, handling the authorization, settlement, and funding of credit card and electronic payments. Common types of payment processors include front-end processors, which manage the initial stages of transaction processing, and back-end processors, which take care of settlement and other post-transaction activities. Merchant service providers are entities that offer a range of services including payment processing, thereby also fitting into the classification of payments processors.

In contrast, a "Cardholder manager" typically refers to a system or function related to the management of cardholder information and relationships, rather than a processing entity in itself. This distinction highlights why it is not considered a type of payments processor. Understanding this functional differentiation is essential for grasping the structure of the payments industry and the roles of various entities within it.