Frank owns a fast-food franchise. Many of the employees who work at Frank's restaurant are young people who take the job as a way to enter the workforce and then move on quickly to other jobs. Frank has a group health insurance plan for his employees, but does not want to deal with the cost, paperwork and record-keeping needed to add these short-term employees to the plan. Which of the following is the most appropriate way to deal with this problem for Frank? a probationary period an eligibility period a minimum participation requirement a full-time work requirement