Which of the following attacks does Unicast Reverse Path Forwarding prevent?

Man-in-the-Middle attacks involve intercepting traffic in transit, which uRPF does not address because it only validates source IP reachability at ingress.

ARP poisoning operates at Layer 2 and manipulates the ARP cache; uRPF operates at Layer 3 and has no mechanism to inspect or validate ARP traffic.

Broadcast storms are caused by switching loop conditions and are mitigated by Spanning Tree Protocol, not uRPF.

uRPF works by checking the routing table to confirm the source IP of an incoming packet is reachable via the interface it arrived on. If the source address is not reachable through that interface, the packet is dropped as likely spoofed. This directly prevents IP source address spoofing attacks used to hide attack origins or bypass access controls.