“Who made your T-shirt?” A Geo letdown University students raised that question. Pietra Rivoli , a professor of business , wanted to find the answer . A few weeks later , she bought a T-shirt and began to follow its path from Texas cotton . rim to Chinese factory to charity bin （慈善捐赠箱）. The result is an interesting new book , The tran’s of a T-shirt in the Global Economy（经济）.
      Following a T-shirt around the world in a way to make her point more interesting , but it also frees Rivoli from the usual arguments over global trade . She goes wherever the T-shirt goes , and there are surprises around every corner . In China, Rivoli shows why a clothing factory , even with its poor conditions , means a step towards a better are for the people who word there . In the colorful used-clothing markets of Tanzania , she realizes that . “it is only in this final stage of life that the T-shirt will meet a real market,” where the price of a shirt changes by the hour and is different by its size and even color . Rivoli’s book is full of me able people and scenes , like the noise , the bad air and the “muddy sweet smell（泥土香味）of the cotton . ”She says ,“ Here in the factory , Shanghai smells like shallot water Texas .”
      Rivoli is at her best when making those sorts of unexpected connections . She even finds one between the free traders and those who are against globalization . The changes opened up by trade are vase , she argues, but free markets need the correcting force of politics to keep them in check . True economic progress needs them both .
59. What does the word “them” underlined in the last paragraph refer to ?
A. Free markets.
B. Price changes.
C. Unexpected connections.
D. Chances opened up by trade.