Which device converts customer routes into VPNv4 routes and advertises them via MP‑BGP?

The Provider Edge (PE) router is the correct answer because it sits at the edge of the service provider's network and connects directly to the customer's network (CE router). The PE router is responsible for receiving customer IPv4 routes, converting them into VPNv4 routes by adding a Route Distinguisher (RD), and then advertising these VPNv4 routes to other PE routers within the service provider's network using Multiprotocol BGP (MP-BGP). This process ensures VPN isolation and scalability. A VPNv4 RR (Route Reflector) is used to simplify the MP-BGP peering within the service provider's core but does not perform the conversion itself. A P (Provider) router is a core router that forwards MPLS packets based on labels but does not process customer routes or MP-BGP VPNv4 updates. A CE (Customer Edge) router is on the customer's premises and sends standard IPv4 routes to the PE, but it does not handle VPNv4 routes or MP-BGP.