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
Dried Semen stains on clothes identified by: 
Select and explain. 
A. Spectrometry, B. UV rays, C. Infrared rays, D. LASER
B: UV rays
Answer: B: UV rays 
Explanation: B i.e. UV rays When examined under filtered ultraviolet (UV) light, seminal fluid (semen) show a fluorescence of bluish white colourQ, which is not specific as other albuminous materials such as nasal, leucorrhoeal discharges, detergents and stains of urine also fluoresce.