Following information are known abot a metal `M :`
`I.` A salt of metal M is used in the manufacture of gunpowder.
`II.` The superoxide of metal M is used as an air purifier in submarines.
`III.` The hydroxide of metal M is used for the absorption of gases like `CO_(2),SO_(2)`, etc. in eudiometry.
Identify the metal M `:`
A. Sodium
B. Calcium
C. Magnesium
D. Potassium