Which option describes the incorrect usage of the Label Distribution method?

Which option describes the incorrect usage of the Label Distribution method?

A.
LDP is primarily used in internal networks of MPLS-VPN providers.

B.
MP-BGP is used for label distribution for VPN customer routes.

C.
Directed LDP is used for label distribution in L2-VPN Attachement Circuits.

D.
MP-BGP is used for label distribution in MPLS Traffic Engineered networks.