Knowledge of which of the following would be most useful in judging the accuracy of the conclusion? A. The number of parakeets in the United States. B. The number of parakeet owners in the United States. C. The number of parakeet owners per hundred people in the country that ranked first in the census. D. The number of parakeet owners in the United States compared to the numbers of owners of other pet birds in the United States. E. The numbers of parakeet owners per hundred people in the countries not included in the census.