Greenhouse gases and climate change – UGC NET Question

Statements A, B, D and E are correct and consistent with basic climate science. Statement A correctly lists major anthropogenic greenhouse gases, statement B explains how they trap outgoing long-wave radiation, statement D points to human-induced enhancement of global warming and statement E recognises the protective role of stratospheric ozone. Statement C is incorrect because the natural greenhouse effect is essential for maintaining Earth’s mean temperature at a habitable level. Therefore, the only combination that includes all true statements while excluding the false one is A, B, D and E.

Option A:
Option A is incorrect because it includes A, B and D but omits E. While A, B and D are indeed correct statements, E is also correct as stratospheric ozone shields living organisms from harmful ultraviolet radiation. By leaving out a true statement, this option does not fully capture the set of correct statements.

Option B:
Option B is correct because it includes statements A, B, D and E, all of which are scientifically accurate. It excludes statement C, which falsely portrays the greenhouse effect as entirely harmful and ignores its natural role in maintaining habitable temperatures. Hence, this option represents the complete and precise set of correct statements asked for in the question.

Option C:
Option C is incorrect because it adds statement C to the set of otherwise correct statements A, B and D. Statement C is wrong since the greenhouse effect in its natural form is beneficial and only its anthropogenic enhancement is problematic. Including a false statement makes this combination unacceptable.

Option D:
Option D is incorrect because it combines B, C, D and E. Although B, D and E are correct, the presence of statement C, which misrepresents the greenhouse effect as wholly harmful, makes the entire combination wrong. A valid answer must exclude all incorrect statements.