Explanation
https://www.cisco.com/c/en/us/support/docs/quality-of-service-qos/qos-policing/19645-policevsshape.html Traffic shaping limits the rate of traffic that is sent or received over a network connection by buffering and delaying the flow of data packets. This will help to ensure that the customer is not exceeding the 100Mbps CIR that the ISP has set and also prevent the aggressive dropping of traffic. Traffic shaping will also help to maximize the bandwidth usage while still staying within the limits of the CIR.

The correct design uses IPv4 unicast for Company A and Company B and VPNv4 in the shared core. In an MPLS Layer 3 VPN architecture, customer edge routing toward the provider edge commonly uses the ordinary IPv4 unicast address family. The PE router then places the learned customer routes into the appropriate VRF. Across the shared provider core, MP-BGP carries those customer routes as VPNv4 prefixes by adding route distinguishers, which keep identical or overlapping customer prefixes unique. Route targets then control which VRFs import or export each route. Cisco describes this VRF and VPNv4 model as the mechanism that prevents one VPN customer from learning another customer's prefixes while sharing the same provider backbone. VPNv4 is not normally used directly between the customer networks and their CE- facing sessions. Therefore, the customer sides use IPv4 unicast, and the shared core uses VPNv4 to preserve separation. Reference topics: MPLS Layer 3 VPN, MP-BGP VPNv4, VRF, route distinguisher, route targets, customer route isolation.