A 23-year-old White female with cystic fibrosis (FEV₁ 65% predicted, pancreatic insufficiency on enzyme replacement therapy) presents with her first cousin to discuss reproductive planning. Family history reveals both parents are carriers; the cousin's parents include one carrier and one unaffected individual. The couple is unaware of their exact carrier status relationship. What is the recurrence risk for cystic fibrosis in their first child?

1. A)1/4
2. B)1/2
3. C)1/24GABARITO
4. D)1/8
5. E)1/16