Which standard outlines requirements for securely handling credit card transactions?

The standard that outlines requirements for securely handling credit card transactions is the Payment Card Industry Data Security Standard, commonly known as PCI DSS. This standard is crucial for organizations that accept, process, store, or transmit credit card information. PCI DSS establishes a comprehensive framework to protect cardholder data and ensure that sensitive financial information is managed securely.

This framework requires businesses to implement various security measures, such as maintaining a secure network, regularly monitoring and testing networks, and implementing strong access control measures. By adhering to PCI DSS, organizations can minimize the risk of data breaches and fraud related to credit card transactions, thereby fostering trust with their customers.

Other options like GDPR (General Data Protection Regulation) focus on data protection and privacy for individuals in the European Union, PHI regulations govern the handling of protected health information, and PII standards revolve around protecting personally identifiable information. None of these specifically address secure handling of credit card transactions like PCI DSS does.