Use the Following to Answer Question

Multiple Choice

Use the following to answer question:
-(Figure: Supply and Demand in Agriculture) Use Figure: Supply and Demand in Agriculture.If a price floor at P₄ is set to help improve farm incomes and the government wants to assure farmers that their output will be purchased,the government must purchase an amount of output equal to:

A) Q₃ - Q₀.
B) Q₃ - Q₁.
C) Q₂ - Q₁.
D) Q₁ - Q₃.