Thank you for reporting, we will resolve it shortly
Q.
$3 : 1 $ratio in $F_2$-generation is explained by
Principles of Inheritance and Variation
Solution:
$3:1$ ratio in $F_2$-generation can be explained by the
law of dominance. It states that, only dominant allele
shows its effect even in the heterozygous condition and
masks the effect of recessive allele. In the given ratio, $3$
represents the dominant phenotype, while $1$ represents
the recessive phenotype.