GTM private IP versus public IP in GTM DNS answers

Just some questions more about this topic;

What in case if you want to resolve a host A record(wide IP) to two different public IP addresses for inbound load balancing purposes across a high available internet connection in one datacenter that contains diferent unique public IP addresses?

You will have the internal private IP address configured as a virtual server in the DMZ, if I am correct using the Irule https://devcentral.f5.com/wiki/iRules.GTM-Translation.ashx you can only resolve to one public IP address instead of the private one to make it work? Is is possible to return more public IP addresses for inbound load balancing using two internet connections?

What will happen if one internet link fails how does the Irule script know which public IP to return that is available(not down)?