What is the correct count of ports scanned by default in Nmap?

• A. 100 ports
• B. 65,535 ports
• C. 1,000 ports
• D. 10,000 ports

Answer: (C)

Nmap scans the 1000 most commonly used ports by default. This choice gives a practical balance between speed and useful information: you get coverage of the services you’re most likely to encounter without the long wait of testing every single port. Scanning all 65,535 ports would take much longer and often isn’t necessary for a quick assessment, while scanning only a small subset (like 100) could miss important services. If you need to broaden or narrow the scope, you can adjust with -p to specify ports or range, or use --top-ports to change how many of the most common ports are checked, or -p- to scan all ports.