CBSE 2025 · Region 4 · Set 2 · Q4 · 1 mark
A colourblind man marries a woman with normal sight who has no history of colourblindness in her family. What is the probability of their son being colourblind ?
Official answer
From CBSE’s own marking scheme for this paper.
(C)
Nil
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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.