CBSE 2025 · Region 1 · Set 3 · Q12 · 1 mark
Which of the following is correct for the condition when plant YyRr is back crossed with the double recessive parent ?
Official answer
From CBSE’s own marking scheme for this paper.
(D)
$\displaystyle 1$ : $\displaystyle 1$ : $\displaystyle 1$ : $\displaystyle 1$ ratio of phenotypes and genotypes
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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.