CBSE 2025 · Region 1 · Set 1 · Q16 · 1 mark
Assertion (A) : When the two genes in a dihybrid cross are situated on the same chromosome, the proportion of parental gene combinations is much higher than non-parental type.
Reason (R) : Higher parental gene combinations can be attributed to crossing over between two genes.
Official answer
From CBSE’s own marking scheme for this paper.
(C)
(A) is true, but (R) is false.
Principles of Inheritance and VariationInheritance of Two GenesUnderstandassertion_reasonmedium
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CBSE Class 12 Biology past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.