Final answer:
FICA taxes are mandatory for earning employees regardless of age. Retirement benefits can be claimed upon reaching older age, but FICA taxes are not contingent on the age of the employee, hence the correct answer is D. None of the above.
Step-by-step explanation:
An employee is not subject to Federal Insurance Contributions Act (FICA) tax merely due to reaching a certain age. FICA taxes, which fund Social Security and Medicare, are generally mandatory regardless of age for all employees who earn a wage.
The Social Security program itself provides benefits to workers upon reaching retirement age, which was initially set at 65 but has been gradually increased to 67 for those born after 1959. Therefore, the correct answer to when an employee is not subject to FICA tax is D. None of the above.