Concept:Price elasticity of demand equal to
0 means perfectly inelastic demand.
Explanation:When the coefficient of price elasticity of demand is
0, the quantity demanded does not change when price changes.
The demand curve is therefore a vertical straight line.
In a standard demand graph, price is shown on the vertical axis and quantity on the horizontal axis.
A vertical line is parallel to the price axis.
Answer:Option B: parallel to the price axis.