-The Above Figure Shows Supply and Demand Curves for Milk

-The above figure shows supply and demand curves for milk.In an effort to help farmers,the government passes a law that establishes a $3 per gallon price support.To maintain the price support,government must purchase

A) Q₁ gallons.
B) Q₂ gallons.
C) Q₁ - Q₂ gallons.
D) Q₂ - Q₁ gallons.