Question: What is the correct format for deriving an Element Manager (EM) Fully Qualified Domain Name (FQDN) in a scenario with multiple vendors?
Option 1: em.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Option 2: vendor<ViD>.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Option 3: em.vendor<ViD>.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Option 4: vendor<ViD>.em.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org
Explanation: The correct format for deriving an EM FQDN in a scenario with multiple vendors is by adding the <vendor ID> label in front of the "em" label, resulting in vendor<ViD>.em.oam.mnc<MNC>.mcc<MCC>.3gppnetwork.org. This ensures that each Element Manager from different vendors can be uniquely identified within the operator's OAM realm domain name.