Which of the Following Statements Are True

Multiple Choice

Which of the following statements are true?

A) Whenever there is positive dependence within pairs, the denominator for the paired t statistic should be smaller than for t of the independent-samples test.
B) When data is paired, the paired t confidence interval will usually be narrower than the (incorrect) two-sample t confidence interval.
C) If there is great heterogeneity between experimental units and a large correlation within experimental units, a paired experiment is preferable to an independent-samples experiment.
D) If the experimental units are relatively homogeneous and the correlation within pairs is not large, an independent-samples experiment should be used.
E) All of the above statements are true.