This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology Pa 1 (Immune Response, Antigen-Antibody Reactions, Hypersensitivity, Structure of Immune System, Immunodeficiency Disorders), Subject name: Microbiology
[{'content': 'VDRL is an example of- \nSelect and explain. \nA. Slide agglutination, B. Tube agglutination, C. Slide flocculation, D. Tube flocculation', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Option 3 Option 1, 2 Slide flocculation test: VDRL and RPR tests used for diagnosis of syphilis. 1. Slide agglutination: To confirm the identification and serotyping of bacterial colonies growni n culture. 2. Tube agglutination is routinely used for: Typhoid fever (Widal test): Detects Ab against both H (flagellar) and O (somatic) Ag Acute brucellosis (Standard agglutination test) Blood grouping (ABO and Rh grouping) Option 4 Tube flocculation test: Kahn test used previously for syphilis.', 'role': 'assistant'}]