[Solved] In testing the difference between the means of two normally distributed populations using large,independent random samples with known variances,the correct test statistic to use is: A)Z statistic B)t statistic C)F statistic D)Chi-square statistic E)None of the above Observations: The act of noting and recording something with instruments or the naked eye as part of a scientific or empirical study. Untreated Population: A group in a study or an experiment that does not receive the treatment or intervention being tested. Significance Level: The threshold in hypothesis testing that determines the probability of rejecting the null hypothesis when it is actually true, often denoted by alpha. Treatment Group: In experimental research, a group of subjects who receive the treatment or intervention under study.