5%significant level是什么意思？95%的置信区间？

问题如下：

Jill Batten is analyzing how the returns on the stock of Stellar Energy Corp. are related with the previous month’s percent change in the US Consumer Price Index for Energy (CPIENG). Based on 248 observations, she has computed the sample correlation between the Stellar and CPIENG variables to be -0.1452. She also wants to determine whether the sample correlation is statistically significant. The critical value for the test statistic at the 0.05 level of significance is approximately 1.96. Batten should conclude that the statistical relationship between Stellar and CPIENG is:

选项：

A.significant, because the calculated test statistic has a lower absolute value than the critical value for the test statistic B.significant, because the calculated test statistic has a higher absolute value than the critical value for the test statistic C.not significant, because the calculated test statistic has a higher absolute value than the critical value for the test statistic

解释：

The calculated test statistic is

Because the absolute value of t = -2.3017 is greater than 1.96, the correlation coefficient is statistically significant.