Solved UPSC CDS/OTA Question
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Q · Environmental PollutionMedium · 45s
Which of the following heavy metals is NOT commonly associated with water pollution?
TopicEnvironmental Pollution
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Helium is an inert noble gas, not a pollutant; lead, mercury, and cadmium are well-known toxic heavy metal water pollutants.
Final Answer: Option D — Helium