Question: What action does the Mobile Station (MS) take when timer T3346 is not running, according to the NORMAL-SERVICE substate?
Option 1: The MS initiates a Location Update procedure.
Option 2: The MS sends a Detach request to the network.
Option 3: The MS enters a power-saving mode.
Option 4: The MS initiates GPRS attach or combined GPRS attach procedure.
Explanation: According to the NORMAL-SERVICE substate, when timer T3346 is not running, the Mobile Station (MS) shall initiate GPRS attach or combined GPRS attach procedure. This ensures that the MS can establish a connection with the network and access General Packet Radio Service (GPRS) for data communication.