In the national income accounts, all of the following are classified as government purchases except:

In national income accounts, government purchases refer specifically to the spending on goods and services that government consumes for providing public services or investing in infrastructure. This includes expenditures on items like salaries for government employees, military equipment, and police services.

Payments made to social security recipients are classified as transfer payments, not as government purchases. Transfer payments are funds transferred to individuals without any goods or services being provided in return, which distinguishes them from direct government spending on services or infrastructure.

On the other hand, services provided by a police officer, the services rendered by U.S. senators (who are government employees), and the purchase of military hardware all represent government spending that contributes to the economy's overall output and are thus classified as government purchases.