Question

Which of the following sources of pollution decrease the oxygen level of water? Select the two correct answers.(1 point)
Responses

plant fertilizer
plant fertilizer

toxic metals
toxic metals

animal manure
animal manure

gasoline
gasoline

radioactive substances

Answer 1

The two sources of pollution that decrease the oxygen level of water are:

1. **Plant fertilizer** - It can lead to nutrient runoff, causing algal blooms that consume oxygen when they decompose.
2. **Animal manure** - Similar to plant fertilizer, it can also contribute to nutrient pollution and lead to algal blooms and oxygen depletion.

Both of these can lead to eutrophication, which decreases the amount of dissolved oxygen available in the water.