The uploaded key includes all four options, but option B is not a valid requirement for normal source NAT and should be removed. Source NAT translates the private source address of outbound traffic into a public address before the packet enters the public network. The public-side router therefore needs reachability to the translated public address for return traffic, not a route to the original private intranet address. By contrast, A can prevent access if NAT is not applied on the proper outbound interface or direction. C can also prevent translation when the configured address pool has no usable address available, depending on the NAT mode and session requirements. D is valid because traffic whose source address does not match the NAT policy or referenced ACL will not be translated; private-source packets then normally cannot traverse the Internet as intended. Routing on the enterprise egress device must of course also be correct, but the specific absence described in B is not inherently a failure when source NAT is working. The verified selections are A, C, and D.