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: Radiology
Earliest sign of fetal life is best detected by 
Select and explain. 
A. X-Ray, B. Feto scopy, C. Real time USG, D. Doppler
D: Doppler
Answer: D: Doppler 
Explanation: D i.e. Doppler Doppler is an interpretation of audible signals of USG By listening fetal hea sounds and seeing blood flow, we can detect fetal life at earliest.