Answer:
C: The stimulation of agriculture by technological innovation
Explanation:
The popularity of Champa rice can be marked to centuries ago when there were not more types of rice cultivated. Champa rice was introduced to the southern part of China from Southern Vietnam. One of the advantages of this crop was that it facilitated double cropping as it matured in less duration. The adoption of machinery and equipment helped to grow the crop in an enormous quantity. Improvement in the irrigation facilities also helped the crops t flourish and grow in a large amount.
The answer is D) They organized an airlift of supplies that lasted almost a year.
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