Final answer:
The ISO/IEC 27001 standard is the most useful for ensuring information security management systems follow industry best practices.
Step-by-step explanation:
The most useful standard for ensuring information security management systems follow industry best practices is the ISO/IEC 27001 standard.
ISO/IEC 27001 provides a framework for establishing, implementing, maintaining, and continually improving an information security management system (ISMS) within the context of the organization's overall business risks. It sets out the criteria for a systematic approach to managing sensitive company information, ensuring its confidentiality, integrity, and availability.
Other standards that can be useful include NIST Cybersecurity Framework and PCI DSS.