In general, the best long-lasting approach to settling project conflict is the _ approach?

It is E - Problem solving & thanks for the invite.

In my opinion

E. Problem solving

Problem Solving approach which is also called as Collaborating approach of Conflict resolution is the long lasting approach to resolve conflicts.

compromising is the best approach

Conflicts are inevitable. As a project manager, it is your job to monitor and resolve conflicts in the early stage to avoid them from becoming a major issue.

From all options, the collaboration and problem solving approach to conflict is the most productive technique. This technique has two major benefits; the conflict itself is solved and the project team is strengthened as a by-product of working to solve the problem. This technique is most likely to be successful in situations where the project team already has a high level of trust. 

The definition of Problem Solving approach: “Incorporating multiple viewpoints and insights from differing perspectives; requires a cooperative attitude and open dialogue that typically leads to consensus and commitment.”

So, answer "E" is correct one.

B. Compromise -------------------------

Thanks for invitation

 I Agree answers Option E