OG7 阅读 Q21

In the fourth paragraph, Brynjolfsson asserts, "Productivity is at record levels, innovation has never been faster, and yet at the same time, we have a falling median income and we have fewer jobs." In order to evaluate his statement that today "we have fewer jobs," figure 2 would need to include accurate information about the number of jobs held by people employed in factories from 1960 to 2011. Without knowing those numbers, it's not possible to determine whether Brynjolfsson's statement is correct.
Choice A is incorrect because a comparison of the median income of all three nations' factory workers within a single year would not aid in the evaluation of Brynjolfsson's statement regarding changes in worker productivity over a span of 10 to 15 years. Choices C and D are incorrect because knowing either the types of organizations where those outputs were measured or which specific manufacturing jobs might have been lost to new technologies would not be helpful in evaluating Brynjolfsson's statement about how median incomes have fallen and job growth has reduced over time.