A Lessons Log is used to capture knowledge gained during a project that can be used to improve future performance. An appropriate entry should provide insight based on experience that can help avoid issues or improve efficiency in future projects. Option B is the most suitable choice because it provides feedback on suppliers that should be avoided based on previous experiences, which is valuable information for future project planning and supplier selection. The other options either provide factual information about the current project or describe the project's scope, which are not lessons learned.