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
Menstruation is defined as precocious if it stas before the child reaches the age of : 
Select and explain. 
A. 8 years, B. 10 years, C. 14 years, D. 20 years
B: 10 years
Answer: B: 10 years 
Explanation: Ans. is b i.e. 10 years