In 2020, new 5G compatible cell phones become available. For a given supply, the equilibrium price of a cell phone A. falls and the equilibrium quantity increases if the demand for cell phones decreases B. rises and the equilibrium quantity increases if the demand for cell phones increases C. falls and the equilibrium quantity increases if the demand for cell phones increases D. falls and the equilibrium quantity decreases unless service providers increase supply E. and the equilibrium quantity are determined by the producers