This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Identification, Subject name: Forensic Medicine
Two identical twins will not have same - 
Select and explain. 
A. Fingerprints, B. Iris color, C. DNA copies, D. Blood group
A: Fingerprints
Answer: A: Fingerprints 
Explanation: There is one chance in 64000 millions of two persons having same fingerprints. It is always unique for each person. ref : Dr.K.S.Narayana Reddys Synopsis of Forensic Medicine & Toxicology 27th edition pg. 47.