This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Law & Medicine, Identification, Autopsy & Burn, Subject name: Forensic Medicine
[{'content': "Hess's rule is useful for detection of: \nSelect and explain. \nA. Fetal weight, B. Fetal age, C. Fetal length, D. Fetal movements", 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. b (Fetal age). (Ref. Textbook of FMT by Parikh 6th ed. 5.67)Hess's rule# CRL of embryo or fetus is based on Hess's rule, which states that square root of length of fetus in cm gives approximate age of fetus in months in first 5 months of pregnancy.# After 5 months it is length in cm/5= age (months).", 'role': 'assistant'}]