Explain how each event shifts either the demand curve or the supply curve. China's rapid economic growth and the massive building of infrastructure shift the A. supply curve to the left as less copper should be produced due to new technologies available. B. demand curve to the right as economic growth is always based on more efficient usage of resources. C. supply curve to the left as economic growth increases the problem of scarcity. D. demand curve to the right because of increase in needs for copper used in production