Researchers were investigating whether there is a significant difference between two medications, R and S, designed to reduce fleas found on cats. From a sample of 300 cat owners, the researchers randomly assigned 150 cat owners to use medication R on their cats and the remaining cat owners to use medication S. For the cats using medication R, 88 percent had no fleas. For the cats using medication S, 90 percent had no fleas. Which of the following is the most appropriate method for analyzing the results?
A two-sample z -test for a difference in population proportions
A two-sample z-test for a difference in sample proportions
A one-sample z-test for a sample proportion
A one-sample z-test for a population proportion
A one-sample z-test for a difference in sample proportions
