Answer:
Conversion at the option of the issuer.
Explanation:
If the issuer determinates the conversion then, it will only do it in favorable scenarios where the conversion cost is lower than paying the bonds thus, by that definition; a bad scenario for the bondholder as they can see the bond converted into a stock that is crashing if it is a issuer will.
Conversion works the other way around is the bondholders whom decides the conversion. In that manner, they will only convert if consider the company share be worth more than the bond