This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diagnosis in obstetrics, Subject name: Gynaecology & Obstetrics
[{'content': 'Banana and lemon sign is seen in : \nSelect and explain. \nA. Neural tube defect, B. Hydrops fetalis, C. Twins, D. lUD', 'role': 'user'}, {'content': "Answer: A \nExplanation: The typical ultrasound cranial signs in open spina bifida are 'lemon sign 'and 'banana sign'.Lemon sign is due to scalloping of the frontal bones. Banana sign is the abnormal anterior curvature of the cerebellum. Refer page no 487 of Text book of obstetrics,sheila balakrishnan,2 nd edition.", 'role': 'assistant'}]