When does the long-run aggregate supply curve shift to the left?

• A. When resources are utilized more efficiently
• B. When workforce education programs expand
• C. When there is a decrease in available resources
• D. When technology improves

Answer: (C)

The long-run aggregate supply curve represents the total output an economy can produce when it is at full employment, with all resources fully utilized. A leftward shift in this curve indicates a decrease in an economy’s productive capacity. This situation occurs when there is a decrease in available resources, such as a reduction in labor force, capital, or natural resources. Reduced availability of inputs limits the economy’s potential output, thus shifting the long-run aggregate supply curve to the left.

When resources are utilized more efficiently, it typically results in an increase in the economy's productive capacity, causing a rightward shift in the supply curve. Similarly, expanding workforce education programs enhances the skill set of the labor force, which can lead to higher productivity and also shift the curve to the right. Improvement in technology allows for more efficient production processes and further boosts the economy’s capacity, again shifting the curve to the right. Therefore, these scenarios do not lead to a leftward shift in the long-run aggregate supply curve.