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: Dental
[{'content': 'Colorimetric caries activity test was developed by? \nSelect and explain. \nA. Snyder, B. Hadley, C. Grainger, D. Rosenberg', 'role': 'user'}, {'content': 'Answer: A \nExplanation: LACTOBACILLUS COLONY COUNT TEST\xa0\nThis caries activity test was introduced by Hadley in 1933.\xa0\nCOLORIMETRIC SNYDER TEST\xa0\nSnyder devised this Colorimetric caries activity test in 1951.\nTHE SWAB TEST\xa0\nGrainger et al developed this test in 1965. It has an advantage over other tests in that no collection of saliva is necessary. So it is valuable in evaluating caries activity in very young children.\xa0\nORA TEST\xa0\nThis test was developed by Rosenberg et al in 1989 for estimating oral microbial levels.\nEssentials of preventive and community dentistry\xa0\nSoben Peter\xa0\n5th edition', 'role': 'assistant'}]