The diagram illustrates aggregate demand (AD) together with aggregate supply in the short run (SRAS) and the long run (LRAS). Which row is correct in explaining the cause of a shift in short-run aggregate supply from SRAS to SRAS1 and in long-run aggregate supply from LRAS to LRAS1?
- Achange in AD from W to Y; increase in population
- Bdecrease in raw material costs; improvements in the education of workers
- Cdecrease in wage rates; decrease in immigration
- Dincrease in availability of labour; increase in labour productivity