What type of bond is registered only for its principal amount, requiring interest coupons for payment?

The correct answer identifies a type of bond that is issued without any record of ownership for the interest payments, meaning that it requires physical coupons to be detached and presented for each interest payment. In this case, a coupon bond is structured such that the bondholder must provide a coupon to receive the interest payment, while the principal amount is recorded.

This distinguishes coupon bonds from other types, primarily because they do not directly track ownership of the interest payments, which is a feature of registered bonds that allow for tracking and direct payment of interest to registered owners without additional steps. Negotiable bonds typically refer to bonds that can be transferred freely among investors, and the term "principal bond" is not commonly recognized in standard bond classifications. Thus, the unique characteristic of the coupon bond requiring physical coupons for interest payments solidly supports its identity within the bond market.