What change can you make to ensure that traffic uses the MPLS VPN backbone instead?

Refer to the exhibit.

Your network uses an MPLS VPN backbone with OSPF routing between all PE and CE routers and on the 10Mb backup Inks between the CE routers. You notice that traffic from CE3 to CE2 and CE4 is flowing over the backup links instead of the higher-bandwidth MPLS VPN backbone even when the

is up.

What change can you make to ensure that traffic uses the MPLS VPN backbone instead?
A . Configure a 1GB sham link between PE2 and PE4.
B . Configure a lower cost metric on the provider network’s OSPF-to-BGP redistribution.
C . Configure internal BGP on PE2, PE3 and PE4.
D . Configure 1Gb sham links between PE3 and PE4 and between PE3 and PE2.

Answer: D