Explanation: When you create a virtual machine, the default setting is to create a Network Security Group attached to the network interface assigned to a virtual machine. A network security group works like a firewall. You can attach a network security group to a virtual network and/or individual subnets within the virtual network. Youcan also attach a network security group to a network interface assigned to a virtual machine. You can use multiple network security groups within a virtual networkto restrict traffic between resources such as virtual machines and subnets. You can filter network traffic to and from Azure resources in an Azure virtual network with a network security group. A network security group contains security rulesthat allow or deny inbound network traffic to, or outbound network traffic from, several types of Azure resources. In this question, we need to add a rule to the network security group to allow the connection to the virtual machine on port 8080. References: https://docs.microsoft.com/en-us/azure/virtual-network/security-overview