<u>Answer</u>: Option 3 Coevolution
<u>Explanation</u>:
<em>Coevolution</em> is a process in which two individuals reciprocally affect each other's evolution. In this process the interacting species exert selective pressures on each other thus, affecting their evolution. Due to this reciprocal adaption they become so close that the evolution of one species is affected by the other.
The first one, cause their trying to make it a positive way to reinforce. Which just means their trying to fix something again
Precipitation differences are the factor that does not contribute to "water stress" on the Earth.
<u>Explanation:</u>
- Less ocean water sources, population differences, Scarcity of economic water resources are the factor which leads to water stress on the Earth.
- Precipitation differences do not cause much difference in water stress. So it will not contribute to the water stress.
- An increase in population will cause major water stress because availability drinking water is less in the earth. Population increase can cause a major problem.
