Margaret works for a privately held corporation. She contributes to her employer's retirement savings plan through regular payroll deductions. Her contributions are tax-deferred, and so are her earnings in the plan. Her employer matches part of her contributions. Margaret most likely participates in which of the following types of employer-sponsored retirement plans? 1)Pension plan. 2)Annuity. 3)401(k) plan. 4)403(b) plan