Final answer:
The answer to the student's question is that 75% of the children will have freckles and 50% will be heterozygous for the freckle trait, which is explained using Mendelian genetics and a Punnett square to predict the probability of inheriting the trait.
Step-by-step explanation:
We can understand this genetics problem using Mendelian principles. When two heterozygous individuals are crossed, in this case for the freckle trait (where freckles are dominant), we use a Punnett square to predict the outcomes for their children. Because both parents are heterozygous, their genotypes are Ff, where 'F' is the dominant allele for freckles and 'f' is the recessive allele without freckles.
The possible combinations for their offspring will be:
- FF - homozygous dominant
- Ff - heterozygous (will show freckles)
- fF - heterozygous (same as above, will also show freckles)
- ff - homozygous recessive (will not show freckles)
From this we can deduce that there would be a 75% chance of the children having freckles (FF, Ff, and fF combinations) and a 25% chance of being homozygous recessive and therefore not having freckles. As for heterozygosity, both the Ff and fF combinations are heterozygous, giving a 50% chance for the children to be heterozygous.
Therefore, the correct answer to the question is 75% of their children will have freckles and 50% of their children will be heterozygous. So the correct option is A. 75%, 50%.