Answer:
A. a graph showing that people in capitalist societies tend to create more wealth
Step-by-step explanation:
lets analyze why the other options are not valid:
B. graph showing that people in capitalist societies work longer hours
it won't necessarily mean that working more hours will contribute to having more wealth, today we observe people having to work full time and take further responsibility to face economic needs.
C. primary source that describes how capitalism creates wealth for corporations
An increase in the wealth of corporations will not directly result in benefit for the people, and it creates a perception of less responsibility and commitment from a corporation to its people. Today corporations are evolving in the face of ever-changing market demands and external forces.
D. primary source that explains why there are more capitalist societies than socialist ones
Being the most popular will not necessarily mean being correct, or better, so therefore we are left with the option A , and we see that Capitalism creates more conditions for gaining wealth, mainly it has the potential to innovate and continues to be the prevailing system of our days.