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
[{'content': "All are tests for detecting carbon monoxide in blood except? \nSelect and explain. \nA. Kastle mayer test, B. Tannic acid test, C. Spectrophotometry, D. Hoppe-seyler's test", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Kastle mayer testSpectroscopic examination, Hoppe - Seyler's test (10% NaOH), kunkel's (tannic acid) test and adding water (15 ml) in 2 drops of blood can detect CO.", 'role': 'assistant'}]