Question: In a mobile network, what is a prerequisite for performing CM-procedures for circuit-switched services between a mobile station and the network?
Option 1: Establishment of an LLC (Logical Link Control) connection
Option 2: Activation of Packet-Switched Service
Option 3: Establishment of an MM-connection (Mobility Management connection)
Option 4: Registration with the MME (Mobility Management Entity)
Explanation: For circuit-switched services, the CM-procedures can only be executed if a Mobility Management (MM) connection has been established between the mobile station and the network. This MM-connection is crucial for managing mobility and facilitating communication for circuit-switched services, distinguishing it from the requirements for packet-switched services or GPRS.