which of the following represents the chain of causation for expansionary policy? multiple choice an increase in the money supply reduces the interest rate, which increases investment, which increases real gdp. an increase in investment increases the interest rate, which increases the money supply, which increases real gdp. an increase in the money supply increases investment, which increases the interest rate, which increases real gdp. an increase in real gdp increases investment, which increases the money supply, which reduces the interest rate.