Answer:
Nitric oxide.
Explanation:
Superoxide may be defined as the compounds that contain the superoxide anions like oxygen anion (O2-). This is also known as the reactive oxygen species.
These anions are generated by the immune system to kill the pathogens. These superoxide include the species like NO, NO2. These super oxide anions are toxic to the cell membrane and also plays an important role in the process of ageing.
Thus, the correct answer is option (A).
