A bookstore reduces the price of its best-selling novel from \$20 to \$15, and sales increase from 100 to 150 copies per week. What can be inferred about the elasticity of demand for the novel?

• A. Demand is perfectly elastic, as sales increase significantly.
• B. Demand is unit elastic, as total revenue remains unchanged.
• C. Demand is elastic, as total revenue increases.
• D. Demand is inelastic, as total revenue decreases.

Answer: (C)