In the short run, any fall in EP /P, regardless of its causes, will cause A) an upward shift in the aggregate demand function and an expansion of output. B) an upward shift in the aggregate demand function and a reduction in output. C) a downward shift in the aggregate demand function and an expansion of output. D) an downward shift in the aggregate demand function and a reduction in output. E) an upward shift in the aggregate demand function but leaves output intact.