Which pair of mechanisms are often used together to allow dynamic routing over a secured site-to-site VPN tunnel?

Which pair of mechanisms are often used together to allow dynamic routing over a secured
site-to-site VPN tunnel?

A.
GRE + SSL

B.
VTI + SSL

C.
VRF + SSL

D.
GRE + IPsec

E.
L2TP + IPsec

F.
VRF + IPsec