Which of the following statements is true?

a. Individuals that save in an employer-sponsored retirement plan will have greater after-tax income and wealth than those who do not save in this plan.

b. Employer-sponsored savings plans are beneficial because the employer pays the taxes on the money contributed to retirement savings.

c. Employees must earn a minimum amount from their employer before they can contribute to the retirement plan.

d. Only retirement plans through work provide tax savings.