The single dimension among the Big Five personality factors that would be most appropriate for use in selecting employees across the broadest range of occupations is the conscientiousness factor.

Conscientiousness is a broad dimension that encompasses traits such as responsibility, self-discipline, and organization. These traits are generally seen as desirable in many different occupations and can apply to a wide range of tasks and job requirements. Therefore, conscientiousness is a good predictor of job performance across a broad range of occupations and industries.