JAMB Chemistry 2013 Question 17

In a water body, too much sewage leads to

1. A.a decrease in the temperature of the water which causes death of aquatic animals.
2. B.an increase in the number of aquatic animals in the water.
3. C.an increase in the bacterial population which reduces the level of oxygen in the water.
4. D.a decrease in the bacterial population which increases the level of oxygen in the water.