Which of the following is the correct test statistic to use for a paired-sample t...

The correct test statistic for a paired-sample t test is used when comparing the means of two related groups. The formula for the paired-sample t test is:

t=dˉsd/nt = \frac{\bar{d}}{s_d / \sqrt{n}}t=sd​/n​dˉ​

Where:

dˉ\bar{d}dˉ is the mean of the differences between the paired observations.

sds_dsd​ is the standard deviation of the differences.

nnn is the number of pairs.