Answer:
C: new, higher-yield crops
Explanation:
All of the other answers are problems while C is a positive scenario.
Answer:
The correct answer will be- Crop rotation
Explanation:
When the growth of a type of crop which uses soil nutrients in abundance and then growing another crop in the same filed led to the decrease in the production of the next crop.
Thus farmers adapted to avoid such farming practices and developed a new practice which allowed the land to become fertile again so that the growth of next crop will not be affected.
The practice involved the planting of a crop on a piece of land then leaving the soil ploughed and unsown for a longer period of time and growing corp on another piece of land allowing the time to restore the nutrient content. This practice is known as "crop rotation".
Thus, crop rotation is the correct answer.
The answer is; Warm water moves to the east instead of to the west
Normally, when the waters in the Pacific warm up, the prevailing winds that blow from east to west drag the warm surface currents westwards and upwelling of cold currents occur at the west coast of South America. However, in El Nino, the Pacific ocean waters heat more than usual. The prevailing winds weaken and begin to blow predominantly towards the east. The warm currents are therefore dragged to the east and cause torrential rains in Western coast South Americas.