It is C as to have freckles you have to have a dominant and recessive gene (can be worked out using a punnett square) as the child has 50% of not having freckles like his dad or 50% having freckles like his mom.
male genes(homozygous recessive)
f f
female F Ff Ff
genes
f ff ff
so ff is not having freckles and being homozygous recessive, or Ff having freckles and being heterozygous.
So the child is heterozygous so C
The process is called denaturation.
I hope this helped :)
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