The aggregate-demand curve:

a. has a slope that is explained in the same way as the slope of the demand curve for a particular product.
b. is vertical in the long run.
c. shows an inverse relation between the price level and the quantity of all goods and services demanded.
d. all of the above are correct.

The aggregate-demand curve shows an inverse relation between the price level and the quantity of all goods and services demanded.

Option C

Explanation:

Aggregate demand curve is the curve which shows the demand of the goods and the services by all the consumers demanded in the economy. The aggregate demand curve is the curve which shows an average relation ship between the quantity demanded by the consumers and the level of prices of the goods and the services in the economy. Since this relation ship is an inverse relation ship, there fore this curve is also down ward sloping curve.

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