type of soil and salinity nitrate levels and turbidity human consumption and pH natural disasters and tidal changes
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Which factors can have the greatest effect on the health of a river system?
Possibilities:
- type of soil and salinity
- nitrate levels and turbidity
- human consumption and pH
- natural disasters and tidal changes

nitrate levels and turbidity