There is evidence that refrigerants are present in the stratosphere.

• A. No evidence
• B. There is evidence in the stratosphere
• C. Evidence only in the lab
• D. They are never present

Answer: (B)

Refrigerants can persist for many years and travel upward with atmospheric circulation, reaching the stratosphere. Direct measurements—taken from balloons, aircraft, satellites, and ground-based stations—have detected refrigerants like CFCs and other halogenated compounds in stratospheric air. This real-world data is part of why scientists connect refrigerants to ozone depletion, since the chlorine and bromine they release when they break down catalytically destroy ozone. So there is clear evidence in the stratosphere. The other options contradict observed data: there is measurable evidence, not just in the lab, and they are not never present.