A demand curve which is parallel to x-axis displays elasticity

The correct answer is: A. infinite.

A demand curve which is parallel to the x-axis is a perfectly inelastic demand curve. This means that the quantity demanded of a good is not affected by changes in the price of the good. In other words, consumers are willing to buy the same quantity of the good regardless of the price.

A perfectly inelastic demand curve is represented by a vertical line. This is because the quantity demanded is the same at all prices.

The following are the four types of demand elasticity:

• Perfectly inelastic demand: The quantity demanded does not change at all in response to a change in price.
• Inelastic demand: The quantity demanded changes by a smaller percentage than the price changes.
• Unitary elastic demand: The quantity demanded changes by the same percentage as the price changes.
• Elastic demand: The quantity demanded changes by a larger percentage than the price changes.

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