Answer:
Option (3).
Explanation:
Mark recapture method is used for the estimation of population size of an area. The individuals are identified by some mark on them. The formula of mark recapture method is
N = M * C/ R
Here, N is the number of the individuals, M is the individuals are marked and captured, C is the individual captured again with mark or non mark and R is recaptured marked individual.
The individual with 200 population, 20 are marked for the first time represent the large population size.
Thus, the correct answer is option (3).
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