It identifies the PCI-DSS requirement followed by Myles in the above scenario. PCI-DSS is a set of standards that aims to protect cardholder data and ensure secure payment transactions. PCI- DSS has 12 requirements that cover various aspects of security such as network configuration, data encryption, access control, vulnerability management, monitoring, and testing. PCI-DSS requirement no 5.1 states that "Protect all systems against malware and regularly update anti- virus software or programs". In the above scenario, Myles followed this requirement by installing antivirus software on each laptop to detect and protect the machines from external malicious events over the Internet.