Please explain to me why if A type of bond which is backed by the issuer's general credit standing and is riskier than secured debt. is not the correct answer.

Which of the following accurately describes a debenture?

Multiple Choice

A bond with specific assets pledged as collateral.

A type of bond issued in the names and addresses of the bondholders.

A type of bond which requires the bond issuer to create a sinking fund of assets set aside at specified amounts and dates to repay the bonds.

A type of bond which is backed by the issuer's general credit standing and is riskier than secured debt.

A type of bond that can be exchanged for a fixed number of shares of the issuing corporation's common stock.