Final answer:
The shape of the long-run aggregate supply curve (LRAS) is vertical, indicating that the economy's potential GDP is determined by factors not influenced by the price level, such as technology and workforce skills.
Option 'a' is the correct.
Step-by-step explanation:
The long-run aggregate supply curve (LRAS) represents the full-employment level of real GDP and is depicted as a vertical curve at the potential GDP level.
This implies that in the long run, the economy's output is not influenced by changes in the price level; instead, it is determined by factors such as technology, resources, and workforce skills.
While the short-run aggregate supply curve (SRAS) is upward sloping, indicating a positive relationship between the price level and real GDP in the short run, the LRAS curve is vertical because those factors that determine potential GDP are not affected by the price level.
Therefore, in response to the multiple-choice question, the correct answer is a. Vertical, highlighting that the long-run aggregate supply curve is a depiction of an economy’s potential GDP.