I remember seeing a similar question in some exam reports. D is the right pick because 'reachable-via rx' activates strict uRPF, forcing the packet's source to be reachable via the receiving interface. That matches Cisco's Nexus config for strict mode. If someone has seen it done another way let me know, but pretty sure it's D.

Honestly, Cisco's uRPF config options are easy to mix up-wish the syntax was more intuitive. C or D here. I picked C since it shows 'ip verify unicast source reachable-via any', and from what I remember, sometimes 'any' is used in strict mode examples. Strict mode should check the source on the incoming interface, which does make me doubt this slightly. If I'm missing something with Nexus specifics, let me know.

Probably C, but which mode are they specifically asking for if the requirement was just 'loose' not 'strict' mode? Official guide examples could flip it for me.