题目解析:
A 选项用 price of rice 定位到:the average price per kilogram doubled,dboubled 对应 A 选项的 increase。
B 选项用 amount of rice 对应该段第4句话:
The average annual volume of rice exported from Siam grew from under 60 million kilograms per year in the late 1850s to more than 660 million kilograms per year at the turn of the century. grew 对应 B 选项的 increase。
C 选项用 nutritional quality 定位,原文中没有提及。
D 选项用 amount of land 定位到该段的最后一句:This growth was achieve as the result of the collective decisions of thousands of peasants families to expand the amount of land they cultivated, clear and plant new land, or adopt more intensive methods of agriculture. expand 对应 D 选项的 increase。