Answer:
The correct answer is option a.
Step-by-step explanation:
In the long run, the aggregate level of output does not change with a change in demand. An increase in demand causes the price level to increase. But the aggregate output level increases only when the availability of resources increases or there is an improvement in the state of technology or both.
An increase in price due to increased demand does not cause the supply to increase as the input prices increase as well.