Question: What is the correct composition of the Service Announcement Fully Qualified Domain Name (FQDN) for Bootstrapping MBMS Service Announcement, specifically when the Mobile Network Code (MNC) has only 2 significant digits?
Option 1: mbmsbs.mnc012.mccXXX.pub.3gppnetwork.org (where XXX represents the actual MCC)
Option 2: mbmsbs.mnc12.mccXXX.pub.3gppnetwork.org (no padding for MNC)
Option 3: mbmsbs.mnc0012.mccXXX.pub.3gppnetwork.org (incorrect placement of padding)
Option 4: mbmsbs.mccXXX.mnc012.pub.3gppnetwork.org (swapped order of MCC and MNC)
Explanation: According to the specifications, when the Mobile Network Code (MNC) has fewer than 3 significant digits, a '0' is inserted at the left side to fill the required 3-digit coding. Therefore, an MNC of '12' would be represented as 'mnc012' in the FQDN, making Option 1 the correct composition, ensuring consistent formatting for DNS translation across different PLMNs.