Solved UPSC CDS/OTA Question
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Q · Modern PhysicsMedium · 45s
Which radioactive element was discovered by Marie Curie? Option: 21
TopicModern Physics
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Marie Curie discovered polonium and radium.
21
Final Answer: Option C — Polonium
21