Given below are two statements, an Assertion (A) and a Reason (R). Choose the correct answer.
Assertion (A):As a result of biomagnification, the secondary consumers will be the most toxic.
Reason (R):The contaminants in biomagnification may be heavy metals such as mercury and arsenic, and pesticides such as polychlorinated biphenyls and DDT.
ABoth (A) and (R) are true and (R) is the correct explanation of (A) ✓ Correct
BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
C(A) is true, but (R) is false
D(A) is false, but (R) is true
Correct answer: (A) Both (A) and (R) are true and (R) is the correct explanation of (A)
Explanation
Both the assertion and the reason are true, and the reason explains the assertion.
The assertion holds that biomagnification leaves the higher consumers carrying the greatest toxic load.
The reason lists the culprits as persistent heavy metals like mercury and arsenic and pesticides like polychlorinated biphenyls and DDT.
Because these substances resist breakdown, they concentrate further at each step up the food chain.
That persistence is precisely why top feeders end up the most contaminated.
The near-loss of certain birds of prey was linked to DDT building up through their prey.
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