Patients with Chronic Obstruction Pulmonary Disease (COPD) Volunteered to Be

Multiple Choice

Patients with chronic obstruction pulmonary disease (COPD) volunteered to be tested for exhaled nitric oxide (eNO) while resting and after a 6 minute walk test. Each subject was measured under each condition, and the order of presentation (resting then walking or the other way around) was randomized. Researchers believe the eNO should be higher while walking than resting for COPD patients. The data are summarized in the table below. Assume each of the distributions of eNO - while walking, while resting, and the differences - is not heavily skewed.
-The p-value of the test is less than 0.0001. Write a conclusion in the context of the problem.

A) We have very strong evidence that the true mean difference in exhaled nitric oxide in COPD patients while walking compared to while resting is greater than zero.
B) We have very strong evidence that the true mean difference in exhaled nitric oxide in COPD patients while walking compared to while resting is equal to zero.
C) We have very strong evidence that the sample mean difference in exhaled nitric oxide in COPD patients while walking compared to while resting is greater than zero.
D) We have very strong evidence that the sample mean difference in exhaled nitric oxide in COPD patients while walking compared to while resting is equal to zero.