Billing plan settings for service contracts are maintained in customizing (SPRO Service Billing). The correct answers are C and D.

Assign Billing Plan Type to Item Category (C): Links billing plan types (e.g., periodic) to contract item categories (e.g., SVC1), ensuring the right plan applies.

Define Billing Plan Types (D): Defines the billing plan types (e.g., monthly, ad hoc) with parameters like periodicity.

Why Not the Others?

A: Not a standard activity; might be a typo.

B: Related to utilities, not service contracts.

'Billing plan settings are maintained by defining billing plan types and assigning them to item categories.'