I don't understand how D can be the right answer. It is stated in the Text that the poor production's rate was not noticed until the new government came to power, whereas answer choice D says that the crops which have been grown in country X and which are different from those planted in Y, have always been grown. So, the difference in production has to do with the policies the two countries take and not with the combination of plants grown in each one of those countries.
I think D could only
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I think D could only
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