Government regulations in Nation X require that milk products labeled "organic" come from cows that have access to pasture. Many industrial dairies have begun using the organic label on their products even though their cows spend most of their milk-bearing lives confined to feed lots eating grain. Critics charge that industrial dairy cows spend too little time grazing in pastures for their milk to bear the organic label, but the cows' owners insist that the animals are in good health and show no signs of discontent.

Which of the following would it be most useful to establish in order to determine whether the industrial dairies' use of the organic label complies with government regulations?