If rooms lack ventilation; which gas accumulates

Radon accumulates in unventilated rooms; this question tests environmental knowledge. A radioactive gas; it’s not neon or CO2; B is correct. Understanding gases enhances health awareness; this is vital for exams or safety discussions; radon poses risks; knowing gases aids in scientific analysis; accurate knowledge ensures clarity in conversations about indoor air or health; staying informed strengthens general knowledge; B aligns with the fact.