OG5 阅读 Q27

Choice D is the best answer. The previous question asks about the relationship between conventional agriculture and organic farming, with the answer being that unlike organic farms, conventional farms use synthetic fertilizers. This is supported in lines 61-65("to...farming"): "Conventional agriculture makes use of 171 million metric tons of synthetic fertilizer each year, and all that nitrogen enables much faster plant growth than the slower release of nitrogen from the compost or cover crops used in organic farming." 
Choices A, B, and C are incorrect because the lines cited do not support the answer to the previous question about the relationship between conventional and organic farming, instead describing the efficiency only of conventional agriculture (choice A), discussing one perceived positive aspect of conventional agriculture (choice B), and highlighting a drawback of organic farming (choice C).