Solved UPSC CDS/OTA Question
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Q · Respiratory System medium · 45s
The residual volume is:
TopicRespiratory System
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Residual volume (~1.2 L) is the volume remaining in lungs after maximal exhalation. It prevents alveolar collapse, maintains alveolar patency, and cannot be measured by spirometry directly.
Final Answer: Option A - Air remaining after normal exhalation