Exam 300-620 topic 1 question 199 discussion

A is the correct answer. https://learnduty.com/cisco-aci/aci-multi-pod-overview-and-basics/

Each Pod connects to the IPN through the spine nodes, the IPN can be as simple as a single Layer 3 device or can be built with a larger Layer 3 network infrastructure like a Service Provider network. Since each Pod is running a separate instance of the COOP protocol, this implies that information about discovered endpoints (MAC, IPv4/IPv6 addresses, and their location) is only exchanged using COOP as a control plane protocol between the leaf and spine nodes locally deployed in each Pod. ACI Multi-Pod functions as a single fabric, so, it is key to ensure that the databases implemented in the spine nodes across Pods have a consistent view of the endpoints connected to the fabric, this requires the deployment of an overlay control plane running between the spines and used to exchange endpoint reachability information. Multi-Protocol BGP has been chosen for this function. This is due to the flexibility and scalability properties of this protocol and its support of different address families (like EVPN and VPNv4) allowing the exchange of Layer 2 and Layer 3 information in a true multi-tenant fashion.

A is correct. MP BGP EVPN is syncing information, COOP is storing it locally per pod.