14. John and Mary are planning to start a family. John was married once before, and he and his first wife had a child with cysticfibrosis. The brother of his current wife, Mary, died of cystic fibrosis. What is the probability that John and Mary will have ababy with cystic fibrosis? (Neither John, Mary, nor their parents have cystic fibrosis.)
(A)1/4
(B)1/6
(C)1/8
(D) 1/12
(E)1/16