With MPLS VPNs, if the CE-PE routing protocol is BGP, which statement below is true?

A.
The different customer sites must use different autonomous system numbers.

B.
Manual route redistribution between EBGP and MP-BGP is required.

C.
The SOO extended BGP community can be used to prevent routing loops.

D.
A BGP virtual sham-link is required between the customer site’s CE routers to ensure optimal routing between the customer sites.

E.
The customer’s autonomous system number must match the MPLS VPN service provider’s autonomous system number.