Which of the following is vital for marketing a union positively?

The importance of finding ways to sell and promote effectively lies in the ability to convey the union's values, successes, and offerings to both potential members and the community. Effective marketing helps to create a positive image, attract new members, and foster support from the public. This involves using various strategies to communicate the benefits of union membership, highlight achievements, and demonstrate the union's role in advocating for workers' rights and interests.

While the other aspects—transparency in operations, the ability to negotiate contracts, and engagement with local businesses—are indeed important for the overall functioning and reputation of the union, they do not directly address the specific task of marketing. Transparency fosters trust, contract negotiations demonstrate the union's strength and effectiveness, and engaging with local businesses can build community relationships; however, without effective promotion and communication strategies, these elements may not translate into a positive public perception or increased membership. The focus on how to effectively sell and promote is crucial in actively shaping a favorable narrative about the union.