Final answer:
Coalition building is the public health intervention being implemented when a nurse promotes alliances among organizations for a common purpose.
Step-by-step explanation:
The public health intervention being implemented when a nurse promotes alliances among organizations for a common purpose is coalition building. Coalition building is the process of bringing together different organizations, groups, or individuals to work collaboratively towards a common goal. In the context of public health, this could involve partnering with community organizations, healthcare providers, and government agencies to address a specific health issue or promote general health and well-bei: