CBSE 2023 · Region 3 · Set 3 · Q16 · 1 mark
Assertion (A) : Mary Mallon continued to spread typhoid for many years.
Reason (R) : Salmonella typhi generally enters the small intestine through food and water contaminated with it.
Official answer
From CBSE’s own marking scheme for this paper.
(A)
Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
Human Health and DiseaseCommon Diseases in HumansUnderstandassertion_reasonmedium
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CBSE Class 12 Biology past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.