How should you configure the multi-exit discriminator (MED) values to enable this failover path?

Your company has a Virtual Private Cloud (VPC) with two Dedicated Interconnect connections in two different regions: us-west1 and us-east1. Each Dedicated Interconnect connection is attached to a Cloud Router in its respective region by a VLAN attachment. You need to configure a high availability failover path. By default, all ingress traffic from the on-premises environment should flow to the VPC using the us-west1 connection. If us-west1 is unavailable, you want traffic to be rerouted to us-east1.

How should you configure the multi-exit discriminator (MED) values to enable this failover path?
A . Use regional routing. Set the us-east1 Cloud Router to a base priority of 100, and set the us-west1 Cloud Router to a base priority of 1
B. Use global routing. Set the us-east1 Cloud Router to a base priority of 100, and set the us-west1 Cloud Router to a base priority of 1
C. Use regional routing. Set the us-east1 Cloud Router to a base priority of 1000, and set the us-west1 Cloud Router to a base priority of 1
D. Use global routing. Set the us-east1 Cloud Router to a base priority of 1000, and set the us-west1 Cloud Router to a base priority of 1

Answer: A