The nmap -sV --version-light target_ip command is the best choice because the -sV flag enables service version detection on open ports, which helps identify running services. The --version-light option is used to make the version scanning faster and with less network overhead by only trying the most likely probes that will identify a service, instead of trying all available probes. The -O flag is for OS detection, not specifically service detection. The -A flag enables OS detection, script scanning, and traceroute, which makes it a heavier and more time-consuming operation, while nmap -F target_ip performs a fast scan of only the most common 100 ports and won't provide service versions.