Some dairy farmers in the province of Takandia want to give their cows a synthetic hormone that increases milk production. Many Takandians, however, do not want to buy milk from cows given the synthetic hormone. For this reason Takandia's legislature is considering a measure requiring milk from cows given the hormone to be labeled as such. Even if the measure is defeated, dairy farmers who use the hormone will probably lose customers, since __. Which of the following, if true, most logically completes the argument? ['it has not been proven that any trace of the synthetic hormone exists in the milk of cows given the hormone', 'some farmers in Takandia who plan to use the synthetic hormone will probably not do so if the measure were passed', "the legislature's consideration of the bill has been widely publicized", 'milk from cows that have not been given the synthetic hormone can be labeled as such without any legislative action']