Question: What type of diagnosis is not performed on the EPS NAS message container information element in the REGISTRATION REQUEST message for 5GS mobility management?
Option 1: Semantical and syntactical diagnosis
Option 2: Presence and length check only
Option 3: Syntax analysis and semantic validation
Option 4: Message integrity verification
Explanation: According to the specifications, no semantical or syntactical diagnosis other than presence and length shall be performed on the EPS NAS message container information element in the REGISTRATION REQUEST message for 5GS mobility management. This means that only basic checks are performed, and more detailed analysis is not done.