Final answer:
The primary function of the Federal National Mortgage Association (FNMA) is to buy mortgages in a secondary mortgage market.
Step-by-step explanation:
The primary function of the Federal National Mortgage Association (FNMA), also known as Fannie Mae, is to buy mortgages in a secondary mortgage market. FNMA is a government-sponsored enterprise that purchases mortgage loans from lenders, such as banks and credit unions, and packages them into mortgage-backed securities (MBS) for sale to investors. By buying these mortgages, FNMA provides liquidity to the mortgage market and helps facilitate homeownership by making funds available for new loans.