Which Statement Best Explains the Logic Behind the Catch-Up Effect

Multiple Choice

Which statement best explains the logic behind the catch-up effect?

A) Workers in countries with low incomes will work more hours than workers in countries with high incomes.
B) The capital stock in rich countries deteriorates at a higher rate because it already has a lot of capital.
C) New capital adds more to production in a country that doesn't have much capital than in a country that already has much capital.
D) Poor countries tend to save a higher share of their income than rich countries.