This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Biological Materials & Stains, Subject name: Forensic Medicine
[{'content': 'Specimen containing viral particle is preserved in? \nSelect and explain. \nA. NaCl solution, B. Formaldehyde, C. 50% glycerine, D. Liquid nitrogen', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. (c) 50% glycerineRef. Textbook of forensic medicine and toxicology: Principles and practice by vij 4/e, p 33', 'role': 'assistant'}]