Implementing ingress filtering verifies that incoming packets are from a source IP address that is reachable via the actual path the packet takes to enter the network, which helps prevent IP spoofing. Using anti-malware software, while helpful against various threats, does not specifically target IP spoofing. Restricting physical access to network devices is a critical aspect of security but does not directly address the issue of IP spoofing. Enforcing strong password policies is important for user authentication but does not prevent the misuse of IP addresses.