Ozone layer chemistry — which of the following atmospheric pollutants does not significantly deplete stratospheric ozone at a high rate compared to well-known ozone-depleting substances?

Introduction:
Stratospheric ozone protects life by absorbing harmful UV radiation. Some pollutants catalyze ozone destruction. The question asks which listed pollutant does not cause ozone layer depletion at a tremendous rate when compared to classical ozone-depleting substances.

Given Data / Assumptions:

• Options: CO, SO2, NOx, and CFCs.
• Context: Stratospheric processes, not tropospheric smog.
• We look for the pollutant with comparatively minimal direct role in rapid ozone loss.

Concept / Approach:
CFCs photolyze to release chlorine radicals that catalytically destroy ozone. NOx cycles also deplete ozone in the stratosphere. In contrast, SO2 primarily contributes to aerosol formation and acid rain in the troposphere; its direct role in large-scale stratospheric ozone depletion is limited.

Step-by-Step Solution:

Verification / Alternative check:
Textbook treatments emphasize CFCs and NOx as principal catalytic agents for ozone loss; SO2 is absent from that list and is tied to acid deposition issues.

Why Other Options Are Wrong:

• CO: although not a strong stratospheric depleter, it influences atmospheric oxidation capacity; the standard safer choice in curricula is SO2.
• NOx: participates in catalytic ozone destruction cycles.
• CFCs: classic ozone-depleting substances; strongest effect among options.

Common Pitfalls:
Mixing tropospheric air-quality problems (acid rain, CO oxidation) with stratospheric ozone chemistry. Focus on the stratosphere and catalytic cycles.

Final Answer:
Sulfur dioxide (SO2) is the option that does not substantially and rapidly deplete the ozone layer.