The correct answer is (c), radiator. A radiator is a heat exchanger that transfers heat from a fluid to a surrounding medium, such as air. In a car, the radiator is used to cool the engine coolant, which is a mixture of water and antifreeze. The coolant is circulated through the engine by the water pump, and then it passes through the radiator, where it is cooled by the air that is flowing through the radiator fins. The cooled coolant then returns to the engine, where it absorbs heat from the engine and carries it back to the radiator to be cooled again.
A polygraph is a device that measures and records various physiological changes such as blood pressure, pulse, respiration, and skin conductivity during an interview. It is often used in law enforcement to detect deception.
A turbine is a machine that converts kinetic energy into mechanical work. It is often used in power plants to generate electricity.
A quadrant is a quarter of a circle. It is often used in geometry to measure angles.