The --open option shows which port states?

The --open option shows which port states?

• A. Open ports only
• B. Open, open|filtered, and unfiltered ports
• C. All ports including closed
• D. Closed ports only

Answer: (B)

The option controls which port states are shown in the results, filtering out clearly closed ports and focusing on ports that are not definitively closed. In Nmap’s terminology, a port can be open, open|filtered (ambiguous due to a firewall), or unfiltered (reachable but not clearly open or closed). Using this filter means you’ll see ports that are truly open, potentially open (open|filtered), or accessible (unfiltered), while closed ports disappear from the list. That’s why the correct choice lists open, open|filtered, and unfiltered ports.

The option controls which port states are shown in the results, filtering out clearly closed ports and focusing on ports that are not definitively closed. In Nmap’s terminology, a port can be open, open|filtered (ambiguous due to a firewall), or unfiltered (reachable but not clearly open or closed). Using this filter means you’ll see ports that are truly open, potentially open (open|filtered), or accessible (unfiltered), while closed ports disappear from the list. That’s why the correct choice lists open, open|filtered, and unfiltered ports.