Of the following, which is considered an uncontrollable expenditure?
a)government operations
b)national defense
c)entitlements
d)salaries for federal employees

The answer is letter c. Entitlements. The biggest uncontrollable expenditure in the federal budget is the Social Security system. 
The United States federal budget contains a large number of expenditures, including mandatory programs such as the Medicare and Social Security programs, military spending, and discretionary funding for Cabinet Departments. These programs such as Social Security benefit, Medicare and Medicaid are called “entitlements’.