This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
Craniopagus is defined as fusion of: 
Select and explain. 
A. Head and spine, B. Head only, C. Thorax and spine, D. Thorax only
B: Head only
Answer: B: Head only 
Explanation: Ans: B. Head onlyRef: Coran Pediatric Surgery 7u ed., pg. 1728Craniopagus:Extent of union:Cranial neuroporeSkull venous sinus &meninges l00%Cerebral coex 37%