The next free private IP automatically assigned from the AppSubnet range is correct because when a virtual machine is deployed into a subnet and no static private address is configured the platform assigns the next available private IP from that subnet range to the VM's network interface.

By default Azure assigns a private IP from the subnet to the VM. The assignment is made from the subnet address space and the platform reserves a small set of addresses for infrastructure, so the actual first usable address can be influenced by those reservations.

A public IP from Azure public address pool is incorrect because a public IP is not automatically assigned from the public pool unless you explicitly attach a Public IP resource to the VM or its network interface.

192.168.5.2 is always the first address given on a new virtual network is incorrect because there is no fixed first address that applies to all virtual networks. The assigned private IP depends on the subnet CIDR and on which addresses are already reserved or in use.

An unpredictable address that cannot be determined in advance is incorrect because the address is chosen from the known subnet range and you can predict or control it by checking the subnet allocation state or by assigning a static private IP when you create the network interface.

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