Which regulatory compliance aspect focuses on customer data security?

The Payment Card Industry Data Security Standard (PCI DSS) is the correct choice as it specifically addresses the security of customer data related to payment card transactions. PCI DSS was established to protect cardholder information and sets comprehensive requirements for security management, policies, procedures, network architecture, and software design. Organizations that handle credit card transactions must comply with these standards to ensure the integrity and security of sensitive data.

In contrast, while the Consumer Financial Protection Bureau focuses on protecting consumers in financial markets, it is not solely centered on data security. The Financial Stability Oversight Council primarily concentrates on monitoring the financial system's stability and systemic risk, rather than individual aspects of data security. Similarly, the Federal Deposit Insurance Corporation aims to protect depositors and ensure the stability of financial institutions, but it also does not specifically address customer data security in the way that PCI DSS does. Thus, the clarity and focus of PCI DSS on payment data protection make it the relevant choice regarding customer data security.