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[A] : There is a chemical warfare amongs...

[A] : There is a chemical warfare amongst some plants .
[R] : The roots or decomposing litter exudates some toxic materials which keep the other plants out of its sphere of influence .

A

If both A and R are true and R is the correct explanation of A

B

If both A and R are true but R is not the correct explanation of A

C

If A is true and R is false

D

If both A and R are false

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TRUEMAN BIOLOGY-Ecology -ASSERTION AND REASON
  1. [A] : Epiphytes are not found in Delhi . [R] : Delhi has semi-arid c...

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  2. [A] : Water logged soils are physiologically dry . [R] : When the s...

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  3. [A] : There is a chemical warfare amongst some plants . [R] : The ro...

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  4. [A] : Total biomass on land is much more than that in water . [R] :...

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  5. [A] : Epiphytes differs from Lianas in that they are not rooted in th...

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  6. [A] : Biological indicators enhance usefulness of ecology to mankind ...

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  7. [A] : Depletion of ozone layer results in human disease like cancer ....

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  8. [A] : UV irradiation to disinfect polluted waters is not generally re...

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  9. [A] : A species is an interbreeding population which is reproductively...

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  10. [A] : Plants having capacity to withstand wide range of temperature t...

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  11. [A] : Each food-level in an ecosystem is called trophic level . [R]...

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  12. [A] : Biomonitoring is reliable for determing the pollutants in air ,...

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  13. Assertion (A) : Tropical rain forests are disappearing fast from devel...

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  14. [A] : Leaf butterfly & stick insect show mimicry to dodge their enemi...

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  15. [A] : In a food chain , membrane of successive higher levels are fewer...

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  16. Assertion (A) : Methane component of greenhouse gases contributing to ...

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  17. Assertion: Suspended particulate matter(SPM) is an important pollutant...

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  18. Assertion : Age sex structure of human population in countries like Fr...

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  19. Assertion (A) : Presently, the global atmosphere is warming up. Reas...

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  20. [A] : Ozone depletion at the south pole will threats world's fisheries...

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