Answer:
The correct answer is letter "D": Junk bonds.
Step-by-step explanation:
A junk bond is a debt security that is poorly rated because it has a high default risk. Junk bonds are also called high-yield or speculative bonds. These are considered riskier investments than higher-rated bonds and thus offer a higher interest rate per year.
Junk bonds can be issued by corporations or governments and have a principal amount, maturity date, and coupon but they are not linked to specific assets as collateral.