In this situation, the CEO is confronted with a conflict that is affecting the entire organization. To effectively address this issue, the CEO should adopt a management style that focuses on conflict resolution and collaboration. Here are the steps that can be taken using an appropriate management style:

1. Adopt a Collaborative Approach: The CEO should use a collaborative management style, which emphasizes open communication and teamwork. This style helps in finding a win-win solution that satisfies both parties involved in the conflict.
2. Facilitate Open Communication: Organize a meeting with both the head of sales and the CEO to discuss the issues openly. Encourage them to express their concerns and listen to each other's perspectives without interruption.
3. Identify the Root Cause: Work with both executives to identify the underlying causes of the conflict. Understanding the root cause is crucial for finding a lasting solution.
4. Mediate and Find Common Ground: Act as a mediator to help both parties find common ground and agree on mutual goals. Highlight the importance of teamwork and the impact of their conflict on the organization.
5. Develop a Resolution Plan: Collaboratively develop a plan that outlines the steps each party will take to resolve the conflict. Set clear expectations and timelines for resolving the issues.
6. Follow Up and Monitor Progress: Regularly check in with both executives to monitor progress and ensure that the resolution plan is being followed. Provide support and guidance as needed to prevent future conflicts.
7. Encourage a Positive Work Environment: Promote a culture of respect, collaboration, and open communication throughout the organization to prevent similar conflicts in the future.

By adopting a collaborative management style and following these steps, the CEO can effectively resolve the conflict and improve the overall work environment within the organization.