问题如下：
When there is a decrease of price level on the aggregate demand curve,
选项：
A. the interest rate will the decline.
B. the interest rate will increase.
C. the interest rate will not change.
解释：
A is correct.
When the price level is decreasing, LM curve will shift to right and intersect with IS curve at a lower interest rate.
考点：AD曲线
解析：当价格水平下降时，表明真实货币供给减少，LM曲线发生向右平移。与IS曲线交于更低的位置，这个位置对应的利率水平就更小，所以A选项正确。
这在聊AD曲线，怎么突然跳到LM去了啊