Faced with the evidence of poor working conditions and low wages in the border maquiladoras, economists __________.
A、shrug their shoulders and ignore the issue.
B、agree that trade theory is thus proven hollow and internally inconsistent.
C、argue that U.S. consumers should not consume lettuce.
D、argue that the poor conditions and low wages are actually improvements for the Mexican workers, and may be cited as gains-from-trade.