In the most simplest answer it is organism
Answer:
The law of conservation of mass states that matter can not be created or destroyed in a chemical reaction.
Explanation:
Reactivity of Group 1 and 2 elements increases as you go down the periodic table. So sodium is more reactive than lithium. Sodium will react with oxygen forming Na2O (sodium oxide). Lithium forms lithium oxide (Li2O).
It’s definitely B but I’m not sure