Which statement is correct about the GRE tunnel endpoints while configuring GRE over IPsec?

Which statement is correct about the GRE tunnel endpoints while configuring GRE over IPsec?

A.
For high availability, the GRE tunnel interface should be configured with a primaty and a backup
tunnel destination IP address.

B.
A mirror image of the IPsec crypto ACL needs to be configured to permit the interesting enduser traffic between the GRE endpoints.

C.
The tunnel interface of both endpoints needs to be in the same IP subnet,

D.
The tunnel interface of both endpoints should be configured to use the outside IP address of
the router as the unnumbered IP address.