Which two statements describe primary differences between MPLS Layer 2 and Layer 3 VPNs? (Choose two.)
A. Layer 2 VPNs use IPsec tunneling, but Layer 3 VPNs use L2TPv3 tunneling.
B. Layer 2 VPNs use AToM, but Layer 3 VPNs use MPLS/BGP.
C. Layer 2 VPNs use BGP, but Layer 3 VPNs use VPLS.
D. Layer 2 VPNs use L2TPv3 tunneling, but Layer 3 VPNs use GRE tunneling.
E. Layer 2 VPNs use IPsec tunneling, but Layer 3 VPNs use pseudowires to provide tunneling.
