这道题怎么理解，我用S-I-（X-M）=G-T怎么不对？deficit增加 ，I减少或者S增加，为什么不选A？
问题如下图：
选项：
A. 
B. 
C. 
解释：
NO.PZ2018062003000193 问题如下 A current account ficit is least likely causewhiof the following items ? A.High private investment. B.High private savings. C.Low taxes. B is correctThe reasons leto a current account ficit inclu low private saving, high private investment, a government ficit, or a combination of the three. Above all the choices, only high private savings is least likely to contribute towara current account ficit.考点Tra Balance.解析X-M=(S-I)-(G-T)通过上述公式可以得知，较高的 private investment，较低的 private savings 以及较低的 taxes都会引起X-M的降低（ Crrent account ficit ）。 这题 为什么要用这个公式，而不是BOP中的current account?
High private savings. Low taxes. B is correThe reasons leto a current account ficit inclu low private saving, high private investment, a government ficit, or a combination of the three. Above all the choices, only high private savings is least likely to contribute towara current account ficit. 考点Tra Balance. 解析X-M=(S-I)-(G-T) 通过上述公式可以得知，较高的 private investment，较低的 private savings 以及较低的 taxes都会引起X-M的降低（ Crrent account ficit ）。这题怎么看出是在问赤字减少
请问老师，C低税收应该会使得钱流入，应该也不会造成赤字，是否也可以选。
低税收也会造成赤子吧？
