In 2010, a medical research group conducted an experiment to evaluate the effectiveness of acupuncture in treating a chronic intestinal condition. Volunteers with the condition were randomly assigned to either a true acupuncture treatment or a placebo treatment. The placebo treatment mimicked acupuncture but did not involve needle penetration. Random assignment resulted in 78 subjects receiving acupuncture and 75 receiving the placebo. After six treatments over three weeks, patients reported whether they experienced a reduction in the condition. The table summarizes the study data, with expected cell counts in parentheses.

Which of the following is true about the chi-square test for homogeneity?

A. The number of subjects randomly assigned to each treatment is not the same; therefore, it is not appropriate to use a chi-square test for homogeneity across treatment groups.

B. Volunteers do not constitute a random sample from the population of all patients with the chronic intestinal condition; therefore, it is not appropriate to use a chi-square test for homogeneity across treatment groups.

C. Volunteers with the chronic intestinal condition were randomly assigned to each treatment, so the independence condition has been met.

D. Not all of the observed cell counts are large enough to satisfy the conditions for applying the chi-square test of homogeneity.

E. Not all of the expected cell counts are large enough to satisfy the conditions for applying the chi-square test for homogeneity.