Chen et al. conducted a study to evaluate the safety and efficacy of interventional bronchoscopic therapy in adult patients with tracheobronchial mucoepidermoid carcinoma (MEC), a rare airway tumor in adults for which surgery is considered a first-line treatment. Specifically, they compared the changes in the Karnofsky Performance Status (KPS) scorean assessment tool for functional impairment that ranges from 0 (dead) to 100 (normal, no complaints, no evidence of disease)before and after the first interventional bronchoscopic therapy for 11 adult patients with tracheobronchial MEC. The sample data are provided in the table below. 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. To do so, answer each of the following questions.

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 alternative hypothesis H1?

Select one:

a. x1 x2 0

b. x1 x2> 0

c. d 0

d. d> 0

e. 1 2 0

f. 1 2>0

What critical value(s) should you use to test the given hypothesis?

Select one:

a. 1.812

b. 1.645

c. 2.228

d. -1.812

e. -1.645

f. -2.228

g. Both a and d

h. Both b and e

i. Both c and f