On a dedicated subinterface implementation, PE-2 must establish an address-family vrf IPv4 BGP neigh

On a dedicated subinterface implementation, PE-2 must establish an address-family vrf IPv4 BGP neighbor relationship with which router?

A.
CE-1

B.
CE-2

C.
PE-1

D.
PE-IG

E.
CE-1 and CE-2

F.
PE-1 and PE-IG