Which option filters results to show only ports that are open (or possibly open)?

• A. -n
• B. --open
• C. --traceroute
• D. -iL

Answer: (B)

Filtering by port state is what this tests. The option that makes Nmap show only ports whose state is open (or possibly open) is --open. Nmap reports each port as open, closed, filtered, or open|filtered, and this switch restricts the display to those ports that are open or potentially open, making reachable services stand out. Other switches don’t filter by port state: -n disables DNS resolution, --traceroute shows the hop path to the host, and -iL reads targets from a file. So the --open option is the one that narrows the results to open (or possibly open) ports.