Monetary neutrality means that a change in the money supply a) does not change real GDP. Most economists think this is a good description of the economy in the short run and in the long run. b) does not change real GDP. Most economists think this is a good description of the economy in the long run but not the short run. c) does change real GDP. Most economists think this is a good description of the economy in the short-run and the long run. d) does change real GDP. Most economists think this is a good description of the economy in the long run but not the short run.