Answer: By beginning each line with a type of worker
Explanation: You can eliminate answer choice A, because the first line of the excerpt begins with “those,” while the other sentences begin with “the.” Answer choice B cannot be valid because Whitman lists the type of worker at the beginning of such line, as opposed to the end. Answer choice D can easily be eliminated because each line ends with a different word, and none are the same. Therefore, you are left with answer choice C, which is clearly the correct answer, as mechanics, carpenters, masons, and boatman are all brought up within the first three words of each sentence.