Solved UPSC CDS/OTA Question
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Q · The Universe medium · 45s
What causes the redshift observed in distant galaxies?
TopicThe Universe
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Redshift occurs because galaxies move away from Earth, stretching emitted light to longer wavelengths due to universal expansion.
Final Answer: Option B - Movement away from Earth due to universe expansion