This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Biostatistics, Subject name: Social & Preventive Medicine
[{'content': 'Descrete variability are all except- \nSelect and explain. \nA. Color of skin, B. Boys in the class room, C. Obesity weight, D. Leukocyte count', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Descrete variables: Have fixed values no intermediate values eg: no. of brothers, no. of children,etc', 'role': 'assistant'}]