They built dams which enabled them to control the flow of water and conserve water for future cases where a drought comes. So far it has been useful even though dams can be controversial because of natural habitats of animals that usually get affected.
“A problem that cash crop agriculture has on the environment is that of soil erosion. With farmers plowing more and more land in order to grow more and more crops, the soil had nothing holding it down. In a more natural ecosystem, the various grasses, weeds, and trees helped to keep the soil intact, and in place. But when the fields were plowed, and the trees cut, there was nothing to keep the soil there anymore. The rains wash the soil into the streams and rivers, causing water quality depletion, and choking the waterways with sediment. Again the ripple effect will continue to grow from within the rivers, which help to damage more ecosystems downstream from the farms as well as those the farms effect directly. After the good soil has been washed away, farmers no longer get the yield of crops that they desire; so new fields are plowed, and more trees are cut in order to create new fields.”
Based off this- water pollution seems a good answer
Answer:
C
Explanation:
Adaptation was first purposed by Charles Darwin, he stated that as the environment changes the animals will gain adaptations suitable for the environment. Therefore, C is the correct answer.
Have a nice day.
Basically they say "null hypothesis" according to source:
http://www.statisticshowto.com/what-does-it-mean-to-reject-the-null-hypothesis/
