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: Radiology
Ultrasound diagnoses all the following except 
Select and explain. 
A. Anencephaly, B. Down syndrome, C. Placenta prae, D. * Hydatidiform mole
B: Down syndrome
Answer: B: Down syndrome 
Explanation: Ans. Down syndrome