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: Forensic Medicine
Transvaginal USG can detect fetal cardiac activity in: DNB 10; MAHE 12 
Select and explain. 
A. 5 weeks, B. 6 weeks, C. 7 weeks, D. 8 weeks
A: 5 weeks
Answer: A: 5 weeks 
Explanation: Ans. 5 weeks