Answer is B: This snippet is captured from the link below:
"Now that you have selected the hardware and protocol used, you need to configure the Domain Name, Cisco Unified Communications Manager Group, and the Module Information. These are the major fields that are required to register an endpoint via MGCP."
So Cisco has listed the order as [Select Hardware, Protocol then FQDN/Hostname]. in the question, we can see it already told you that Hardware is: VG320, Protocol is :MGCP , the next step has to be Specify FQDN/Hostname
https://www.cisco.com/c/en/us/support/docs/voice/media-gateway-control-protocol-mgcp/214635-configure-and-troubleshoot-mgcp-gateways.html