This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Trace evidences, Subject name: Forensic Medicine
The different semen in case of gang rape is identified by:- 
Select and explain. 
A. Acid phosphatase test, B. Christmas tree stain, C. PSA, D. Single photon flourimetry
D: Single photon flourimetry
Answer: D: Single photon flourimetry 
Explanation: Single photon fluorimetry has been used to differentiate between different semen in a gang rape case TESTS FOR SEMINAL STAINS Creatine phosphokinase test Acid phosphatase testQ Florence testQ (Choline iodide crystals) Barberio's test (crystals of spermin picrate)