A pharmaceutical company has developed a new antiviral drug to relieve Covid symptoms. The company advertises that their new antiviral drug in tablet form will significantly reduce the mean number of days an individual suffers from Covid symptoms. To test their claim, a medical researcher randomly selects 40 individuals who tested positive for Covid on the same day. The 40 individuals are then randomly divided into two equal groups: a treatment group of 20 subjects and a control group of 20 subjects. The individuals in the treatment group are administered the new antiviral drug while the control group individuals are administered a placebo tablet ( that is, a pill that has no effect on reducing Covid symptoms). The researcher records the number of days it takes for each of the 40 individuals to recover from Covid symptoms. The researcher then computes the sample mean and standard deviation number of days for both the treatment and control groups. The sample test results for each group are summarized in the following table.

Summary Test Results for the Treatment and Control Groups

Treatment Group Control Group n1 = 20 n2 = 20 x with bar on top1 = 6.5 x with bar on top2 = 9.3 s1 = 2.5 s2 = 3.9

The researcher decides to perform the 5-step hypothesis testing procedure to determine if the new antiviral drug will significantly reduce the mean number of days an individual suffers from Covid symptoms at = 1%. Assume equal population standard deviations. Let population #1 represent the treatment group and population #2 represent control group.

After conducting the 5-step hypothesis test procedure, the researcher can conclude that:

a. hypothesis test was inconclusive

b. there was no difference in mean number of days an individual suffers from Covid symptoms between the new antiviral drug and the placebo drug

c. the new antiviral drug reduces the mean number of days an individual suffers from Covid symptoms

d. the new antiviral drug increases the mean number of days an individual suffers from Covid symptoms

e. the placebo drug reduces the mean number of days an individual suffers from Covid symptoms