This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Death and Investigations, Subject name: Forensic Medicine
Locard's principle is famous for: 
Select and explain. 
A. Theory of exchange, B. Fingerprint study, C. Formula for estimation of stature, D. System of personal identification using the body measurement
A: Theory of exchange
Answer: A: Theory of exchange 
Explanation: Ans. a. Theory of exchangeRef: APC Essentials of Forensic Medicine and Toxicology by Anil Aggrawal; Page No- 426 and Essential of Forensic Medicine and Toxicology, KSN Reddy, 33rd Ed; Page No-475Locard's Exchange principle states that when any two objects come into contact there is always a transfer of material from each object on to the other.This principle is often used as a sure proof of crime.The principle was first enunciated by Edmond Locard (1877-1996), often referred to as the Sherlock Holmes of France.