Which single parameter, when passed to nmap, will instruct nmap to perform a fast scan? (Provide
only the option)

Answer: -F

Explanation:
From the man pages:
-F (Fast (limited port) scan)
Specifies that you only wish to scan for ports listed in the nmap-services file which comes with nmap
(or the protocols file for -sO). This is much faster than scanning all 65535 ports on a host. Because
this list contains so many TCP ports (more than 1200), the speed difference from a default TCP scan
(about 1650 ports) isn’t dramatic. The difference can be enormous if you specify your own tiny
nmap-services file using the –datadir option.