Which MPLS inter-AS option can achieve this goal?

A client has an MPLS inter-AS implementation that is required to have QoS deployed between ASBRs based on IP packet. At the same time, the client requires minimization of the routing configuration between ASBRs for better scalability.

Which MPLS inter-AS option can achieve this goal?
A . Option A
B . Option B
C . Option C
D . Option AB

Answer: D