Which of the following statements, pertaining to the characteristics of qualified retirement plans, are true? 1. Employer contributions are not subject to federal income tax. II. Employer contributions are not subject to payroll tax. III. Employee pretax contributions are not subject to federal income tax. IV. Employee contributions are subject to payroll tax. OI I, III, and IV only II, III, and IV only OI, II, and III only O I, II, and IV only I, II, III, and IV