A Sign Company Creates and Prints the Full- Sized Vinyl

A sign company creates and prints the full- sized vinyl sheets that make it quick and easy to change the promotion on a billboard.If a change in the price of petroleum (a necessary ingredient for the production of plastic) forced manufacturers of vinyl sheets to increase their price by 20 percent,the company would still need to buy the same amount to meet its customers' needs.Therefore,demand for vinyl sheets by companies that use this product to create billboard ads is .

A) economic
B) elastic
C) fixed
D) imaginary
E) inelastic