Refer to the exhibit.

For asite-to-site IPsec VPN, each peer must point to thereachable IP address of the remote VPN endpoint—that is, the IP address on the WAN/Internet-facing interface of the remote router.

From the diagram:

R1 outside (toward Internet):192.168.10.1

R2 outside (toward Internet):192.168.20.2

Inside LANs:

Site 1:10.1.0.0/24

Site 2:10.2.0.0/24

The crypto map on R1 uses:

crypto map mymap 10 ipsec-isakmp

set transform-set myset

match address 101

set peer

The must be the IP address where R1 can actually reach the IPsec peer, which is R2’s Internet-facing interface192.168.20.2.

If the peer were configured with a LAN IP such as 10.2.0.1 (site 2’s internal gateway), IKE packets would never reach the remote router because that address is not routable over the Internet.

Therefore, the correct command to bring up the VPN is:

set peer 192.168.20.2

Option A (10.1.0.1)– local LAN IP (R1’s side), not the remote endpoint.

Option C (192.168.10.1)– R1’s own WAN IP, not the remote peer.

Option D (10.2.0.1)– remote LAN IP, not reachable directly over the Internet.