An analyst conducts a two - tailed test to determine whether differences between the means of two populations exist: H0: μ1-μ2=0 versus H2: μ1-μ2≠0. Assume that the populations are independent, normally distributed, and have unequal and unknown variances. The critical value with 50 degrees of freedom is 2.126. The computed test statistic is t=1.753. Using a significance level of x=0.05, which of the following statements is TRUE（）
A. Use a t- test to reject the null hypothesis and accept the alternative hypothesis.
B. Use a t -test to accept the null hypothesis and reject the alternative hypothesis.
C. Use a z- test to reject the null hypothesis and accept the alternative hypothesis.
参考答案：B
解析：
The appropriate test is a t -test concerning differences between means. Because the critical value is greater than the computed t - value, the null hypothesis cannot be rejected at the 0.05 level of significance.