Which among the following statement is INCORRECT?

Option B is incorrect. When two linear demand curves intersect each other, they have the same price and quantity at the point of intersection. However, their slopes may be different. Since price elasticity of demand depends on both the slope of the demand curve and the price-quantity relationship, the coefficient of elasticity need not be the same on both demand curves.

Option A is correct: A linear demand curve can depict different degrees of price elasticity, ranging from elastic to unitary elastic to inelastic at different points. The limiting cases of perfectly elastic and perfectly inelastic demand are also represented conceptually by horizontal and vertical demand curves.

Option C is correct: Two parallel linear demand curves have the same slope, but at a particular price they can have different quantities demanded. Since elasticity depends on the price-to-quantity relationship as well as the slope, the coefficient of elasticity can be different for the two curves.

Option D is correct: Price elasticity of demand measures the relative (percentage) change in quantity demanded in response to the relative (percentage) change in price, rather than absolute changes.

Therefore, the incorrect statement is Option B.