Which operating system(s) support(s) unnumbered VPN Tunnel Interfaces (VTIs) for route-based VPN’s?

Which operating system(s) support(s) unnumbered VPN Tunnel Interfaces (VTIs) for route-based
VPN’s?

A.
Solaris 9 and higher

B.
IPSO 3.9 and higher

C.
Red Hat Linux

D.
SecurePlatform for NGX and higher

Explanation: