Question: In a 3GPP-compliant network, which functional element(s) can provide signaling to trigger Content of Communication (CC) interception for a Voice over IP (VoIP) call at a PDN-GW/GGSN or IMS-AGW?
Option 1: P-CSCF
Option 2: IBCF
Option 3: MGCF
Option 4: S-CSCF or AS
Explanation: According to the specified network architecture for lawful interception, when CC interception is required at a PDN-GW/GGSN or IMS-AGW (which have access to voice media), the signaling to generate the trigger for this interception can be provided by the P-CSCF (Proxy-Call Session Control Function). This is because P-CSCF is involved in the call setup and management for these network elements, enabling it to initiate the necessary triggers for lawful interception purposes.