Router R1, a branch router, connects to the Internet using DSL. Some traffic flows through a GRE and IPsec tunnel, over the DSL connection, destined for an Enterprise network. Which of the following answers best describes the router's logic that tells the router, for a given packet, to apply GRE encapsulation to the packet?（）

• A、When the packet received on the LAN interface is permitted by the ACL listed on the tunnel greacl command under the incoming interface
• B、When routing the packet, matching a route whose outgoing interface is the GRE tunnel interface
• C、When routing the packet, matching a route whose outgoing interface is the IPsec tunnel interface
• D、When permitted by an ACL that was referenced in the associated crypto map