Answer:
If the disorder has an autosomal recessive inheritance pattern, according to the family tree both parents do not have the disorder, but are carriers.
Explanation:
When a disorder or disease is recessive it requires<u> two alleles with the disorder to manifest</u>. In this case, according to the pedigree, both parents must be heterozygous carriers and not present the disorder.
<u>Parents
</u>
♂ Dd
♀ Dd
Both without disorder but presenting the altered gene, which makes them carriers.
<em>Alleles D d
</em>
<em>D DD Dd
</em>
<em>d Dd dd</em>
The offspring of these parents have a 50% chance of being carriers without the disorder, 25% non-carriers, and 25% with the disorder.
In the event that either parent was DD, there would be a 50% chance of carriers without the disorder and no chance of offspring with the disorder, which has a recessive inheritance pattern.