When mortgages are sold after they have been funded, they are considered part of the:

The primary mortgage market is where loans are originated, meaning this is where borrowers apply for and receive their mortgages from lenders. Once a mortgage is funded and the loan is created, it does not remain in the primary market; instead, it moves to the secondary market, where it can be sold or traded.

The Rural Housing Service (RHS) is a part of the U.S. Department of Agriculture that provides loans and grants to support rural housing. While it plays a role in financing housing in rural areas, it does not pertain to the buying and selling of funded mortgages, which occurs in the secondary mortgage market.

The Federal Reserve System is the central banking system of the United States, which primarily regulates the economy and monetary policy. While it influences interest rates and lending practices, it does not directly engage in the buying or selling of funded mortgages, which is the function of the secondary mortgage market.