This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Anatomy
Banana and lemon sign is seen in which fetal anomalies : 
Select and explain. 
A. Neural tube defect, B. Hydrops fetalis, C. Twins, D. IUD
A: Neural tube defect
Answer: A: Neural tube defect 
Explanation: Signs of Spina bifida on USG : Small biparietal diameter Ventriculomegaly Frontal bone scalloping or the so called Lemon sign. Elongation and downward displacement of the cerebellum, the so called Banana sign Effacement or obliteration of the cisterna Magna. Ref:Williams Obs 23e pg 354,355.