Final answer:
The two mandatory categories of government spending paid for by FICA taxes are Social Security and Medicare.
Step-by-step explanation:
The two mandatory categories of government spending that are paid for by FICA taxes are Social Security and Medicare. Social Security provides financial support to retired and disabled individuals, while Medicare provides healthcare coverage for the elderly and certain qualifying individuals. These programs are funded by payroll taxes, including FICA taxes.
Learn more about Government spending funded by FICA taxes