An insurance company launched a "Star of Hope" insurance business, which requires parents of 5-year-old children to pay an annual insurance premium of 600 yuan and reach the age of 14 to enjoy all the tuition fees of children going to college in the future. which is the most appropriate reason for parents not to participate in insurance? ['Parents are not sure which university children will attend in the future.', 'The total 10-year cumulative insurance premium is greater than the total tuition for college in the future.', 'It is estimated that the growth rate of tuition fees for college each year is greater than the growth rate of living expenses.', 'This business does not include the cost of boarding.']