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[A] : Methane component of green house g...

[A] : Methane component of green house gases contributing to global warming is about 20 percent .
[R] : Introduction of multi-point fuel injection engines in automobiles has decreased methane content in the exhausts .

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark a

B

lf both Assertion & Reason are true but the reason is no t the correct explanation of the assertion, then mark b

C

If Assertion is true statement but Reason is false, then mark c

D

If both Assertion and Reason are false statements, then mark d.

Text Solution

Verified by Experts

The correct Answer is:
B
Methane is largely a product of incomplete decomposition and is produced by a group of bacteria called methanogens under anaerobic conditions. The major sources of methane include freshwater wetlands enteric fermentation in cattle and flooded rice fields. Biomass burning also produces methane. Major gases contributing in greenhouse effect with their percentage contribution are given in the given pie chart.
Efficient engine (for example, multi point fuel injection engine) can reduce the unburnt carbons (like methane etc.) in auto emission.
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Assertion (A) : Methane component of greenhouse gases contributing to global warming is about 20 per cent. Reason (R) : Introduction of multi-point fuel injection engines in automobiles has decreased methane content in the exhausts.

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