【单选题】Which additional information, if presented in figure 2, would be most useful in evaluating the statement "Productivity is at record levels, innovation has never been faster, and yet at the same time, ...
A.
The median income of employees as it compares across all three countries in a single year
B.
The number of people employed in factories from 1960 to 2011
C.
The types of organizations at which output of employed persons was measured
D.
The kinds of manufacturing tasks most frequently taken over by machines