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: Gynaecology & Obstetrics
Which of the following is the earliest conclusive evidence of intrauterine death : 
Select and explain. 
A. Shrinking of body, B. Intra-aoic gas, C. Increased curvature of spine, D. Spalding sign
B: Intra-aoic gas
Answer: B: Intra-aoic gas 
Explanation: Intra-aoic gas