You have an Azure environment that contains multiple Azure virtual machines.

To implement a solution that enables the client computers on your on-premises network to communicate to the Azure virtual machines, you need to configure a VPN (Virtual Private Network) to connect the on-premises network to the Azure virtual network.

The Azure VPN device is known as a Virtual Network Gateway. The virtual network gateway needs to be located in a dedicated subnet in the Azure virtual network. This dedicated subnet is known as a gateway subnet and must be named ‘GatewaySubnet’.

Note: a virtual network (answer D) is also required. However, as we already have virtual machines deployed in a Azure, we can assume that the virtual network is already in place.

References:

https://docs .microsoft.com/en-us/office365/enterprise/connect-an-on-premises-network-to-a-microsoft-azure-virtual-network