What term describes a form of fixed-interest security issued by various entities?

The term that describes a form of fixed-interest security issued by various entities is a bond. Bonds are essentially loans made by investors to borrowers, which can be governments, municipalities, or corporations. In exchange for the loan, the issuer of the bond agrees to pay a specified interest rate over a specified period and return the principal amount at maturity. This characteristic of providing fixed interest payments makes bonds a popular investment choice for those seeking a stable income over time.

Other choices like common stock and preferred stock do not represent fixed-interest securities. Common stock represents ownership in a company with variable returns based on the company's performance and does not guarantee dividends. Preferred stock may have fixed dividends, but it represents a form of equity rather than debt and does not typically provide the same level of capital security as bonds do. Treasury bills (T-bills) are short-term government securities that are issued at a discount and mature with no coupon payment, differentiating them from traditional bonds which pay periodic interest. Therefore, bonds stand out as the correct answer due to their fixed-interest nature and status as debt instruments issued by various entities.