Imagine a pedigree that traces an inherited disorder found in individuals with two recessive alleles for gene D. The pedigree shows three siblings with the genotypes DD, Dd, and dd. Did the parents of these three children have a disorder?

No

Explanation:

One of the parents would have to have dd in order to have the disorder, since it says the disorder is found in those with two recessive alleles. The parents had a kid with the genotype DD. This means both parents had at least 1 D. Therefore, neither parent's genotype could be dd.