Human resources director: While only some recent university graduates consider work environment an important factor in choosing a job, they all consider salary an important factor. Further, whereas the only workers who consider stress level an important factor in choosing a job are a few veteran employees, every recent university graduate considers vacation policy an important factor. If all of the statements of the human resources director are true, then which one of the following must be true? ['At least some veteran employees do not consider work environment an important factor in choosing a job.', 'At least some people who consider work environment an important factor in choosing a job consider vacation policy an important factor as well.', 'No one for whom salary is an important factor in choosing a job also considers stress level an important factor.', 'All people who consider work environment an important factor in choosing a job also consider salary an important factor.']