You have an Azure environment that contains 10 virtual networks and 100 virtual machines. You need to limit the inbound traffic to all the Azure virtual networks. What should you create?

Azure Firewall is a managed cloud-based network security service that protects your Azure Virtual Network resources. It allows for centralized creation, enforcement, and logging of application and network connectivity policies across subscriptions and virtual networks. By deploying a single Azure Firewall and routing traffic through it, you can control inbound traffic for all linked virtual networks.

Azure ExpressRoute circuits provide private connectivity to Azure services over a dedicated connection, not a mechanism to limit inbound traffic for virtual networks.

Virtual network gateways are used to send traffic between Azure virtual networks and on-premises locations or between Azure virtual networks themselves, not for centralized inbound traffic filtering.

An Application Security Group (ASG) allows grouping virtual machines for network security rules, typically used within Network Security Groups (NSGs) for granular VM-level control, not for centralized inbound filtering across multiple VNets like a firewall.