Question: What is the Domain Name for MC Services confidentiality protection used in a host part of a SIP URI, indicating that the user part contains a confidentiality protected MC Services identity?
Option 1: mc-encrypted.3gpp.org
Option 2: mcptt-encrypted.3gppnetwork.org
Option 3: mc1-encrypted.3gppnetwork.org
Option 4: mcv-encrypted.3gppnetwork.org
Explanation: The Domain Name for MC Services confidentiality protection used in a host part of a SIP URI is "mc1-encrypted.3gppnetwork.org", indicating that the user part contains a confidentiality protected MC Services identity, as specified for protecting MCPTT, MCData, and MCVideo identities.