Final answer:
Employers must withhold Federal Taxes, unemployment taxes, and FICA contributions, which cover Social Security and Medicare, from their employees' wages by law.
Step-by-step explanation:
The employers are legally required to withhold certain amounts from their employees' paychecks, which include Federal Taxes, unemployment taxes, and FICA contributions.
The Federal Insurance Contributions Act, or FICA, requires that the employer and employee split the payroll taxes, with 6.2% deducted for Social Security and 1.45% deducted for Medicare from the employee's wages.
Although contributions toward retirement funds are often made, they are not mandated by law to be withheld by employers.