A penetration tester is performing an Nmap scan on a target system to gather as much information as possible without raising suspicion. The tester suspects the presence of a fairly updated intrusion detection system (IDS) on the network. Which of the following Nmap options should the tester use to perform OS detection in the most efficient manner while maintaining a lower profile?
-T4 -O
--osscan-limit -O -T2
-O
-T2 -O