单选题 The author implies which of the following conclusions?

A、 The Commodity Credit Corporation was created to offer farmers incentives for taking land out of production.
B、 Secretary of Agriculture Wallace alienated members of the American Farm Bureau Federation by proposing an ever normal granary.
C、 The Agricultural Adjustment Act of 1933 was declared unconstitutional because it was written by the Farm Bureau.
D、 Roosevelt's ability to gain passage of the Agricultural Adjustment Act of 1938 depended on the large harvests of 1937.

【正确答案】 D

【答案解析】“Without direct crop controls，agricultural production skyrocketed in l937”正是农业的大丰收以及缺乏有效监控，使得农产品的价格不断下跌，引发危机。罗斯福抓住这一契机使得1938年的AAA获得通过。