Techno Security Inc. recently hired John as a penetration tester. He was tasked with identifying open ports in the target network and determining whether the ports are online and any firewall rule…

The -PP flag sends ICMP timestamp request packets, which performs an ICMP timestamp ping scan rather than a TCP SYN ping scan.

The -PO flag triggers an IP protocol ping scan that probes multiple IP protocol types simultaneously, not a TCP SYN ping.

The -PS flag instructs Nmap to send TCP SYN packets to the target, which is the correct syntax for a TCP SYN ping scan; combined with -sn, it performs host discovery without a full port scan. TCP SYN ping reveals whether hosts are online and can expose firewall rules because a filtered port drops the packet while an open port returns a SYN-ACK response. The leading 'A' in 'Anmap' in this answer choice is a typo in the question stem - the actual command is nmap -sn -PS.

The -PA flag sends TCP ACK packets, which is a TCP ACK ping scan - a distinct technique often used to bypass stateless firewalls, not a SYN ping scan.