Which organization is known for developing international maritime rules?

The International Maritime Organization (IMO) is the specialized agency of the United Nations responsible for regulating shipping. Established in 1948, the IMO's primary purpose is to develop and maintain a comprehensive framework for international shipping, ensuring safety, security, and environmental performance of international shipping operations.

The organization sets global standards for the safety, security, and efficiency of shipping and prevents marine pollution from ships. It achieves these goals by creating conventions and regulations that countries worldwide adopt and implement. This makes the IMO the authoritative body specifically tasked with maritime governance and international maritime rules.

In contrast, the other organizations listed focus on different fields, such as health, education, or humanitarian aid, rather than the specific niche of maritime operations and the creation of shipping regulations. Hence, the IMO stands out as the foremost entity associated with the development of international maritime rules.