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

Explanation:

Because poisonous substance have not oxygen but less

Answer 2

Answer:

oxygen is correct

Explanation:

poisonous substance may not allow oxygen to be in the water