Which of the following statements is correct?

A debenture is a secured bond that is backed by some or all of the firm's fixed assets.

Junk bonds typically provide a lower yield to maturity than investment$-$grade bonds because investor prefer the latter.

Secured debt has a lower priority of repayment than unsecured debt, in the event of bankruptcy, because the latter is free from obligations.

Convertible bonds have higher coupon rates than non$-$convertible bonds of similar default risk because the risk of the former increases on conversion.

Senior debt carries a lower coupon rate than junior debt due to its lower default risk and higher repayment priority.