Question: In a network operating in Mode II, what type of attach procedure does a non-GPRS-attached Mobile Station (MS) use when attempting to attach for GPRS services?
Option 1: Combined RA/LA Update Procedure via CS Domain
Option 2: Normal IMSI Attach with immediate PDP Context Activation
Option 3: GPRS Attach Procedure without prior IMSI Attachment
Option 4: Normal IMSI Attach followed by a separate GPRS Attach Procedure
Explanation: According to the context, in Mode II (or if the MS is not GPRS-attached), the Mobile Station first performs a 'normal IMSI attach'. Only after being IMSI-attached can it then use a separate GPRS Attach procedure to gain access to GPRS services, ensuring the MS is identified and authenticated at the network level before accessing packet-switched services.