Question: In the context of 3GPP charging aspects, what two primary charging approaches can a network operator utilize for end-users or intermediaries?
Option 1: Retail Charging (directly to users) and Wholesale Charging (to 3rd party service providers)
Option 2: Prepaid Charging and Postpaid Charging
Option 3: Session-Based Charging and Call-Based Charging
Option 4: Peer-to-Peer Charging and Server-Hosted Charging
Explanation: This is correct because network operators can employ two main strategies for billing: Retail Charging, where the end-user is billed directly, and Wholesale Charging, where a third-party service provider is charged for services rendered to their customers. These approaches cater to different business models within the telecommunications sector.