You designed IP ranges for private GKE clusters using privately used public IP space due to RFC1918 exhaustion. After designing the IP scheme, what should you do?

The correct answer is to create privately used public IP primary and secondary subnet ranges and create private GKE clusters with --disable-default-snat, --enable-ip-alias, and --enable-private-nodes. Since the design uses privately used public IP space, disabling default SNAT is crucial to prevent IP conflicts and allow direct communication within the private network. --enable-ip-alias is necessary for GKE to use IP aliasing for pods and services, which is standard practice for GKE networking and allows for flexible IP assignments. --enable-private-nodes ensures the cluster nodes have only internal IP addresses, aligning with the private GKE cluster design. The other options are incorrect because they either revert to RFC1918 addresses, which are exhausted in this scenario, or omit critical flags like --disable-default-snat that are essential when using privately used public IP space.