Economist Michael Kremer provides some support for the hypothesis that an increase in population might foster economic prosperity. Which statement best explains this hypothesis?

a.More people can produce more ideas, which contribute to increasing productivity.

b.When there is a large number of children, governments need to invest more in education, which fosters economic growth.

c.A larger population implies more demand for goods and services, which stimulates the economy.

d.More people are able to produce more output, everything else being the same.