When should you disable redistribution of IPv4 routing updates between MP-BGP neighbors?

When should you disable redistribution of IPv4 routing updates between MP-BGP neighbors?

A.
When the network only supports MPLS VPNs.

B.
When the network is using OSPF or ISIS instead of I-BGP as the network IGP.

C.
When you want to reduce the number of labels that the P-router needs to store.

D.
When you want to reduce the number of routes that the P-routers must store in their global BGP routing table.