Question: When can the Mobile Station (MS) resume using extended idle mode DRX cycle (eDRX) after having a PDP context for emergency bearer services deactivated?
Option 1: Immediately after deactivating the PDP context for emergency bearer services.
Option 2: After receiving new eDRX parameters during an attach procedure.
Option 3: Only if the network has provided new extended DRX parameters IE during the last routing area updating procedure.
Option 4: Upon successful completion of the PDP context deactivation procedure for a PDP context for emergency bearer services, and having received the extended DRX parameters IE during the last attach or routing area updating procedure.
Explanation: According to the specifications, if the MS received the extended DRX parameters IE during the last attach or routing area updating procedure, upon the successful completion of the PDP context deactivation procedure for a PDP context for emergency bearer services, the MS shall resume eDRX. This indicates that resumption of eDRX is contingent on both the prior receipt of eDRX parameters and the successful deactivation of the emergency bearer service's PDP context.