This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Obs), Subject name: Gynaecology & Obstetrics
Breathing movement of fetus on USG is first detected on? 
Select and explain. 
A. 11 weeks, B. 20 weeks, C. 24 weeks, D. 26 weeks
A: 11 weeks
Answer: A: 11 weeks 
Explanation: Ans. A. 11 weeksDutta states: "Breathing movements are identified by 11 weeks but are irregular until 20th week. Their frequency varies from 30-70 per minute and is dependent on the maternal blood sugar concentration."