A-A+
A．Agriculture in the industrialized world.B．Cu
问题详情
A．Agriculture in the industrialized world.
B．Cultivated crops.
C．The association between roses and humans.
D．The discoveries of certain grasses.
参考答案
正确答案：B
解析：信息明示题。由文章最后的内容可知，农作物的培育是第一个伟大的进步，所以B正确。
