A rubber hose and one way valve in the emission control system that redirects exhaust fumes back to the engine is known as what?

The correct answer is C, EGR (exhaust gas recirculation). The EGR system is designed to redirect a portion of the vehicle's exhaust gases back into the engine's intake manifold. This process helps reduce nitrogen oxide (NOx) emissions, which are a significant contributor to air pollution, by lowering the combustion temperature. The inclusion of the rubber hose and one-way valve is characteristic of the EGR system as it allows exhaust gases to flow back into the engine under certain conditions while preventing backflow during normal operation.

The other options refer to different components or systems within the vehicle's emission control framework. The EVAP system is responsible for capturing and storing fuel vapors from the fuel tank and preventing them from entering the atmosphere. The PCV system helps ventilate the crankcase and recirculate unburned gases back into the intake manifold for combustion. The catalytic converter is a component that transforms harmful exhaust gases into less harmful emissions before they exit the vehicle. Each of these operates under different principles and for different purposes within the overall emissions control strategy.