On March 1, 2021, a corporation has published a Notice of Redemption, calling all of its 6 1/2% Debentures, maturing in 2031. The corporation plans to refund the issue with new bonds at a lower interest rate. A bondholder can:

A bondholder can sell the bonds he is holding at the current market price.

Explanation:

When it occurs that bonds are called, there will  no longer be interest payments on the bonds called. A bondholders then has the option to either sell the bonds he is holding at the current market price or the bonds can be tendered to receive the call price.

In addition, it is also not possible to exchange the old bonds for the new refunding bonds. By implication, any investor that needs the new bonds needs to go and buy it in the market.

Based on the explanation above, it simply means that a bondholder can sell the bonds he is holding at the current market price.