Which of the Following Questions Should a Successful Model Predict

Multiple Choice

Which of the following questions should a successful model predict?
i. Why, in general, do Americans have higher incomes than Africans?
ii. How much less unemployment is there during an economic expansion?
iii. Why does the United States have a lower unemployment rate than Europe?

A) i and ii
B) ii only
C) iii only
D) i, ii, and iii
E) i and iii