Paper notes bought by an individual backed by a promise by the government to repay the money with interest after a certain period of time are called
a. stocks.
c. greenbacks.
b. tariffs.
d. bonds.

D. BONDS

Bonds are paper notes bought by an individual backed by a promise by the government to repay the money with interest after a certain period of time.

Bonds available for investments are:
1) US Government Securities / government bonds
2) Municipal bonds
3) Corporate bonds
4) Assets-and-Mortgage backed securities
5) Federal Agency Securities
6) Foreign Government bonds

Bonds are also known as bills, notes, debt-securities, and debt obligations. 

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