Question

*When water becomes unclean and poisonous due to mixing of natural or artificial unwanted material, the amount of ___________ decreases.*

1️⃣ Nitrogen
2️⃣ Oxygen
3️⃣ Hydrogen
4️⃣ Carbon dioxide​

Answer 1

Answer:

oxygen is the answer

maybe it is correct

Answer 2

the answer is :

oxygen

hope it's help uh...