It is better to identify a “Trained and certified professional”. The advantage is that, the employee would have already to trained to work in office environment by learning various courses observing various skills like ethics, problem-solving, collaboration (working in teams), etc. So this in turn would enable to work independently with all the essential skills.
Undergraduate: This option would not help because he is a graduate who does not have any experience so each and everything of how to work independently, how to work in teams, how to report the work, etc should be taught in on-the-job training and it will take time for the employee to get settled.
College student: This is once again not a smart choice, since both education and work ethics might not be higher or as expected and it might take its own time to get settled.
Hardworking person: This might be right sometimes but a graduation is important if it involves professional / dynamic work rather than a routine work.