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
When two objects come in contact, an exchange of trace material takes place. This is known as: PGI 08 
Select and explain. 
A. Galton exchange, B. Locard exchange principle, C. Beillion system, D. Hasse rule
B: Locard exchange principle
Answer: B: Locard exchange principle 
Explanation: Ans. Locard exchange principle