Given below are two statements: one is labelled as Assertion A and the other…
2026
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Eutrophication leads to depletion of dissolved oxygen in a lake.
Reason R: Dissolved oxygen in water decreases with increase in temperature.
In the light of the above statements, choose the most appropriate answer from the options given below:
नीचे दो कथन दिए गए हैं: एक को अभिकथन A और दूसरे को कारण R के रूप में अंकित किया गया है।
अभिकथन A: यूट्रोफिकेशन (Eutrophication) से झील में घुली हुई ऑक्सीजन (Dissolved Oxygen) की कमी हो जाती है।
कारण R: पानी में घुली हुई ऑक्सीजन तापमान में वृद्धि के साथ कम हो जाती है।
ऊपर दिए गए कथनों के आधार पर, नीचे दिए गए विकल्पों में से सबसे उपयुक्त उत्तर चुनें:
- A.
Both A and R are correct and R is the correct explanation of A
A और R दोनों सही हैं और R, A की सही व्याख्या है
- B.
Both A and R are correct but R is NOT the correct explanation of A
A और R दोनों सही हैं, लेकिन R, A की सही व्याख्या नहीं है
- C.
A is correct but R is not correct
A सही है, लेकिन R सही नहीं है
- D.
A is not correct but R is correct
A सही नहीं है, लेकिन R सही है
Attempted by 18 students.
Show answer & explanation
Correct answer: B
Assertion A is correct because eutrophication leads to oxygen depletion in water bodies due to the bacterial decomposition of excess organic matter. Reason R is also scientifically accurate as dissolved oxygen solubility in water decreases with an increase in temperature. However, the primary mechanism for oxygen loss during eutrophication is biological consumption by decomposers rather than thermal effects on solubility. Therefore, while both statements are true, Reason R does not correctly explain Assertion A.