Question: What triggers an NF instance to send an Nnrf_NFManagement_NFUpdate Request message to the NRF?
Option 1: When the NF instance is initialized.
Option 2: After a scaling operation, when the NF instance's capacity has been updated.
Option 3: Periodically, at a fixed interval.
Option 4: Manually, by an administrator via the OAM system.
Explanation: According to the procedure described in Figure 4.17.2-1, an NF instance sends an Nnrf_NFManagement_NFUpdate Request message to the NRF when its updated NF profile needs to be informed to the NRF, for example, after a scaling operation that has updated its capacity.