Cystic fibrosis is a genetic disorder. it is a recessive trait that is determined by two alleles. suppose two parents each carry at least one recessive allele, but neither of them has cystic fibrosis. which statement reflects the likelihood of a child of these parents having cystic fibrosis? the child cannot have the disease because only the dominant alleles will be passed on. the child will have the disease because only recessive alleles will be passed on. the child may or may not have the disease because a recessive gene from each parent may be passed on. the child may or may not have the disease because the disease does not depend on the alleles of the parents.

The answer should be C

The child may or may not have the disease because a recessive gene from each parent may be passed on.

Explanation:

Since cystic fibrosis is a recessive genetic disorder and none of the parents have cystic fibrosis is a genetic disorder then it implies that both the parents are carriers for this disease i.e. they are heterozygous for the trait.

The following combination represents their genotype:

                               Mother         Father

Parental                     Aa                Aa

F1 generation      AA     Aa       Aa      aa

So, on the basis of above mentioned combinations of alleles in the F1 generation it is clear that the child might have cystic fibrosis and he/she may not have the disease. If the child will be born with genotypes AA & Aa then he will not have the aforementioned disease but if the child will be born with genotype aa then he will have the disease.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.