33. 關於gastroschisis及omphalocele之比較，何者正確？ (1) gastroschisis形成的原因是因為occlusion of the omphalomesenteric artery (2) gastroschisis形成的原因是因為failure of gut migration from the yolk sac into the abdomen (3) gastroschisis發生率約1 in 6000 births (4) Incidence of associated anomalies，omphalocele約10%-15% (5) gastroschisis容易合併Beckwith-Wiedemann syndrome
(A) 1
(B) 2, 4
(C) 3, 5
(D) 3
(E) 5