Question: What does the EPS attach result IE value "combined EPS/IMSI attach" indicate in an ATTACH ACCEPT message?
Option 1: Attach for EPS services and non-EPS services, or for EPS services and "SMS only", have been successful.
Option 2: Attach for EPS services has failed but attach for non-EPS services or "SMS only" has been successful.
Option 3: Attach for EPS services has been successful but attach for non-EPS services or "SMS only" is pending.
Option 4: The UE needs to re-attach with a different EPS attach result IE value.
Explanation: According to the 3GPP specification, when the EPS attach result IE value indicates "combined EPS/IMSI attach", it means that the attach procedure for both EPS and non-EPS services, or for EPS services and "SMS only", has been successfully completed.