What entity provides a structure for developing and delivering incident-related coordinated messages?

The Joint Information System (JIS) is the correct choice because it facilitates a structured approach to managing and disseminating information during an incident. The JIS allows various organizations and agencies involved in emergency response to coordinate their messages, ensuring that the information provided to the public is consistent, accurate, and timely. This coordination is essential in crisis situations to prevent misinformation and confusion, thus helping to maintain public trust and effectively communicate critical information.

By utilizing the JIS, agencies can work together to share resources and expertise, develop unified messaging strategies, and enhance the overall effectiveness of communication efforts during an emergency. This system integrates multiple entities, such as public information officers and spokespersons from various organizations, to craft and deliver coherent messages that address community needs and concerns during an incident.