The sample standard deviation of the differences between the pretreatment and posttreatment KPS scores is 10.787. Using a 0.05 significance level, you need to test the claim that interventional bronchoscopic therapy improves functional impairment, i.e., that the KPS score is higher after the therapy.

Pretreatment (%) --> 90; 80; 90; 90; 90; 90; 80; 90; 50; 60; 50

Posttreatment (%) --> 100; 100; 100; 100; 100; 100; 100; 100; 80; 100; 80

What is the most appropriate test for the given claim?

a. Two-sample z-test

b. Two-sample (pooled variance) t-test

c. Two-sample (unpooled variance) t-test

d. Paired t-test

e. Wilcoxon rank-sum test

What is the null hypothesis H0?

a. x1 x2 0

b. x1 x2> 0

c. d 0

d. d> 0

e. 1 - 2 0

f. 1 - 2> 0

What is the alternative hypothesis H1?

a. x1 x2 0

b. x1 x2> 0

c. d 0

d. d> 0

e. 1 2 0

f. 1 2>0