Question 922Navigation General

The correct answer is C) A hygrometer. A hygrometer is the instrument used to measure the relative humidity of the air. Relative humidity is a measure of the amount of moisture in the air compared to the maximum amount of moisture the air can hold at a given temperature. Hygrometers detect changes in moisture content and provide a measurement of the relative humidity. The other answer choices are incorrect because: A) A spectrometer is used to analyze the spectrum of light, B) A hydrometer measures the density of liquids, and D) A barograph measures changes in atmospheric pressure over time.