The correct answer is A) scrubber. The scrubber is the component in an inert gas system that is responsible for cleaning the inert gas of solid and sulfur combustion products, while also cooling the gas. The scrubber achieves this by passing the inert gas through a series of baffles or filters, which remove the solid and sulfur contaminants, and by using a cooling mechanism to reduce the temperature of the gas. The other options are incorrect because: B) purifier is a more general term that may not specifically refer to the component responsible for cleaning and cooling the inert gas; C) filter is a more specific component that may not handle the cooling function; and D) cooler is a component that only addresses the temperature reduction, without the cleaning aspect.