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

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

A.
SecurePlatform for NGX and higher

B.
Solaris 9 and higher

C.
IPSO 3.9 and higher

D.
Red Hat Linux

Explanation: