c

fertilizer是要素，价格上升，那么他的需求减少。

B

是单选题吗？是的话其他就不用考虑了。

a. an increase in the supply of fertilizer. Incorrect. There would be an increase in the quantity supplied of fertilizer. b. a decrease in the demand for fertilizer. Incorrect. There would be a decrease in the quantity demanded.

c. a decrease in the supply of sunflowers. Correct. An increase in resource costs reduces the supply.

d. an increase in the supply of sunflower. Incorrect. The increase in resource prices would cause less to be offered for sale at each price.

[此贴子已经被作者于2005-6-5 21:38:10编辑过]

是选c,你所说的Differences between "decrease in the supply of sth." and" decrease in the quantity supply sth." 前者是指供给的变动，后者是指供给量的变动。两者的区别可以从以下几个方面来把握：

1、变动原因：前者是由于价格之外的其他因素所引起的，后者是由于价格的变动引起的

2、几何表现：前者表现为供给曲线的移动，后者表现为供给点在同一条供给曲线上的移动

谢谢gaoxy朋友的讲解，讲的很透彻！再次感谢！！^_^