Bony fish. In other words, fish that are invertebrates.<span />
Answer:
The source of pollution that decreases the oxygen level of water are plant fertilizer and animal manure.
Explanation:
Plant fertilizer that is applied in the agricultural field when enter into the water body, causes water pollution which increases minerals into the water body and animal manure contain raw material which causes eutropication that means increase algal bloom. This indirectly decreases oxygen availability into the water body.
Oxygen, also it helps keep the suns radiation in to keep us warm
