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Which of the following statements descri...

Which of the following statements describe natural extinction ?
(i) Extinctions abetted by human activities
(ii) Slow replacement of existing species
(iii) Also known as background extinction
(iv) A small population is most likely to be extinct
(a) (i) and (ii)
(b) (i), (ii) and (iii)
(c) (ii), (iii) and (iv)
(d) (i), (ii), (iii) and (iv)

A

(i) and (ii)

B

(i), (ii) and (iii)

C

(ii), (iii) and (iv)

D

(i), (ii), (iii) and (iv)

Text Solution

Verified by Experts

The correct Answer is:
C
Natural or background extinction is a slow process of replacement of existing species with the better adapted species due to alternate evolution, changes in environmental conditions, predators and diseases. A small population due to inbreeding depression (reduces genetic variability) and normal population fluctuations during unfavourable periods like drought, harsh winter or severe summer.
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