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: Microbiology
[{'content': 'Positive Schick test indicates: \nSelect and explain. \nA. Immune to diphtheria, B. Immune and hypersensitivity to diphtheria, C. Susceptible and hypersensitivity to diphtheria, D. Susceptible to diphtheria', 'role': 'user'}, {'content': "Answer: D \nExplanation: Schick Test: The immune status of a person can be assessed by Schick's test. The test is performed by intradermal injection of 0.1 mL of purified standardized toxin. If the patient has no anti toxin, the toxin will cause inflammation at the site 4 to 7 days later. If no inflammation occurs, antitoxin is present and the patient is immune. A positive schick test indicates susceptible to diphtheria. Ref: Levinson W. (2012). Chapter 17. Gram-Positive Rods. In W. Levinson (Ed),Review of Medical Microbiology & Immunology, 12e.", 'role': 'assistant'}]