A local electronics store recently increased the price of a portable speaker it sells from $15 to $18. The owner of the store noticed that the store went from selling 100 units a month to 70 speakers a month. Which of the following choices correctly describes the price elasticity of demand for the portable speaker?
A. The demand for the portable speaker is unit elastic.
B. The demand for the portable speaker is perfectly inelastic
C. The demand for the portable speaker is price elastic
D. The demand for the portable speaker is price inelastic