NO.PZ2018062016000142
问题如下：
When discerning the difference between population means(samples are not independent), then most accurate test is :
选项：
A.z-test.
B.paired comparisons test.
C.chi-square test.
解释：
B is correct. The t-test in this section is based on data arranged in paired observations, and the test itself is sometimes called a paired comparisons test.
请问不是说所有的判断均值的都用t分布吗？选项里也没有这个选项啊
