<span>D. provide systematic irrigation.</span><span>
Agriculture Science is the science of crop production and its improvement. In Agriculture Science, scientists focus on research and development on various aspects of crop technology and production.
Crop improvements include:
1. Irrigation Management as a production technique
2. Minimizing the growth of pests
3. Transformation of raw products to end-consumer products
4. Prevention of adverse environmental effects (e.g. waste management and soil degradation)
5. Supply and demand for food in a global basis 6. Crop quantity and quality 7. Study of other fields of agriculture (e.g. soil science) </span>
The fact that volcanic rock has often been found early in the rock record but less frequently in later rock layers suggest to scientists the following conclusion about early earth: <span>volcanic activity was more common in the past than it is today.
</span>Besides volcanic activity in general, also huge volcanic eruptions<span> were much </span>more common than today<span>.</span>
My guess would be D. Agriculture.