CO₂ content in soil air is:

✅ Explanation:
-The typical CO₂ content in soil air ranges from 0.1% to 0.4%, significantly higher than the atmospheric CO₂ concentration (around 0.04%).
-This is primarily due to the respiration of plant roots and soil microorganisms, which release carbon dioxide as a byproduct.
-Among the given options, 0.25% falls within this expected range and is thus the most likely answer.