Concept:Price elasticity of demand measures how much quantity demanded responds to a change in price.
Explanation:Elasticity of demand is written as:
Ed=% change in price% change in quantity demandedWhen elasticity is zero,
Ed=0.
This means a change in price causes no change in quantity demanded.
Mathematically, the percentage change in quantity demanded is
0%.
Therefore, consumers buy the same quantity regardless of price changes.
On a graph, this demand curve is a vertical straight line.
This situation is called perfectly inelastic demand.
Answer:The demand curve is perfectly inelastic.
Correct option: B. perfectly inelastic.