Which of the following is an example of a policy required by law?

Health and safety policies are mandated by law to ensure a safe working environment for employees. These policies are designed to comply with legal requirements stipulated by regulations such as the Health and Safety at Work Act in various jurisdictions. They establish guidelines and procedures that employers must follow to prevent workplace injuries and illnesses, ensuring that both employees and visitors are protected from hazards.

In contrast, employee satisfaction policies, social media guidelines, and dress code policies are typically developed at the discretion of the organization. While they are important for maintaining workplace culture and professionalism, they do not carry the same legal requirements or implications as health and safety policies. Thus, only health and safety policies are legally required, making this the correct answer to the question.