NO.PZ2016010801000059
问题如下：
Which of the following factor will least likely expand the long-run aggregate supply in an economy?
选项：
A. an increase in business taxes.
B. An increase in the stock of physical capital.
C. A policy to increase labor force participation rate.
解释：
A is correct. The increase in business taxes will shift SRAS leftward and have no impact on LRAS. The increase in physical capital and labor force participation rate both increase resource base and in the long run, it will shift LRAS rightward.
考点：供给曲线
解析：税收属于成本因素，营业税的增加将使SRAS左移，但是对LRAS没有影响。A选项入选。
实物资本和劳动力参与率的增加都增加了资源基础，从长远来看，这将使LRAS向右移动。B,C选项不入选。
老师请问b选项为什么正确