One of the reasons humans rely heavily on only a few food crops is because
A. There are few edible wild species.
B. It would be difficult for small farmers to cultivate the fragile wild species.
C. We have not explored the cultivation of thousands of edible wild species.
D. We have already focused on the best tasting species for domestication and cultivation.
E. All of these factors contribute to a heavy reliance on only a few species.
Answer: C
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