Answer:
AD shifts left and price level would decrease.
Step-by-step explanation:
If consumer wealth decreases due to a plunge in the stock market, the AD curve will shift to the left. This is because shifts to the left of the AD curve represent a reduction in demand, and if consumers are poorer, they will naturally decrease their demand.
This will in turn reduce the price level, because in a market system, prices will fall until they meet the new, lower demand, meaning that a new equilibrium price is reached.