Question: What information does the new MME extract from the GUTI via the reverse mapping procedure to retrieve the UE's information?
Option 1: IMSI and P-TMSI Signature
Option 2: RAI, P-TMSI, and IMSI
Option 3: Only RAI and P-TMSI
Option 4: GUTI and P-TMSI Signature
Explanation: The new MME extracts only the RAI and P-TMSI from the GUTI via the reverse mapping procedure to retrieve the UE's information, such as the IMSI. This is done to include the mapped RAI and P-TMSI in the corresponding message sent to the old SGSN for identifying the UE.