UPSC CSE Prelims
Question 20
Consider the following statements :
Statement I : Scientific studies suggest that a shift is taking place in the Earth's rotation and axis.
Statement II : Solar flares and associated coronal mass ejections bombarded the Earth's outermost atmosphere with tremendous amount of energy.
Statement III : As the Earth's polar ice melts, the water tends to move towards the equator.
Which one of the following is correct in respect of the above statements?
View correct answer and explanation
Correct answer: B
Correct Option: B (Both Statement II and Statement III are correct but only one of them explains Statement I)
Explanation: Both the solar-activity statement and the redistribution-of-meltwater statement are scientifically valid, but only moving water mass toward lower latitudes directly explains shifts in Earth's rotational axis.
Statement / Pair / Item-wise Analysis:
I: True-the rotation axis can shift as mass redistributes.
II: True-solar flares and coronal mass ejections disturb the upper atmosphere, but do not explain the stated polar motion.
III: True-melting land ice redistributes mass toward the equator and changes the planet's inertia.
Option-wise Analysis:
A. Incorrect-this wrongly treats both supporting statements as valid or assigns an incorrect explanatory relationship.
B. Correct-this matches the facts and the item-wise assessment above.
C. Incorrect-this misstates how many supporting statements are true and explanatory.
D. Incorrect-the item analysis identifies at least one supporting statement as valid.