Valium (diazepam) is a widely prescribed antidepressant and sedative. a study investigated how valium works by comparing its effect of diazepam on sleep in seven knock‑in mice, in which the receptor is insensitive to valium, and in eight wild‑type control mice. the study found that valium reduced sleep latency in both groups with no significant difference between the groups. according to the study authors, this lack of significance "is related to the large inter‑individual variability that is also reflected in the low power ( 20%) of the test."(a) select the best explanation as to why tests having low power often fail to give evidence against a null hypothesis even when the null hypothesis is really false o because a low-power test is more likely to give type i errors. o because we have probably insisted on a significance level that is too small. o because if the difference between the null and the alternative hypotheses is large, it is more difficult to detect it. o because in order to detect an alternative which is close to the null hypothesis we need a high power test.