Consider statements about environment: 1. The ozone layer protects Earth from UV radiation. 2. Greenhouse gases trap heat in the atmosphere. 3. Acid rain is beneficial for soil fertility. Which are correct? MCQ with Answer and Explanation

Consider statements about environment: 1. The ozone layer protects Earth from UV radiation. 2. Greenhouse gases trap heat in the atmosphere. 3. Acid rain is beneficial for soil fertility. Which are correct?
A. 1 and 3 only
B. 1 and 2 only
C. 2 and 3 only
D. 1, 2 and 3
Answer: Option B
Solution (By JKSSB Mock Tests)
The stratospheric ozone layer acts as a vital shield, absorbing the majority of the sun's harmful ultraviolet (UV-B and UV-C) radiation, protecting life on Earth. Greenhouse gases (like CO2, methane, water vapor) absorb and re-emit infrared radiation, trapping heat in the troposphere and maintaining Earth's temperature (the greenhouse effect). Acid rain, containing sulfuric and nitric acids, is highly detrimental; it leaches essential nutrients from the soil, releases toxic aluminum, and damages plant life, reducing soil fertility. Thus, statements 1 and 2 are correct.

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Which of the following diseases can be prevented by the BCG vaccine?
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Consider statements about ecology: 1. A food web consists of interconnected food chains. 2. Decomposers recycle nutrients. 3. Biomass decreases at higher trophic levels. Which are correct?
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Correct Answer: Option C


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