In the network diagram below, which device is the router?

 In the given network diagram, device D is depicted as a cloud symbol, which is commonly used to represent the internet in network diagrams. The router is typically connected to the internet and acts as a gateway for internal network devices to access external networks. Therefore, device D is the router in this context. References: Virtual Router Overview - Palo Alto Networks | TechDocs, Networking (UDRs) in Azure: Inserting the VM-Series into an Azure …, Setting Up the PA-200 for Home and Small Office - Palo Alto Networks …