This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of Health and Disease, Subject name: Social & Preventive Medicine
[{'content': "Pioneer in concept of 'Specific protection by vaccine: \nSelect and explain. \nA. Chinese medicine, B. Robert Koch, C. Ambroise Pare, D. Louis Pasteur", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a) Chinese medicine* Chinese were early pioneers of immunization* They practiced variolation to prevent smallpoxALSO REMEMBERChinese Barefoot Doctors* Farmers who received minimal basic medical and para- medical training and worked in rural villages of China* Name comes from southern farmers, who would often work barefoot in the rice paddies promoted basic hygiene, preventive health care, family planning and treated common illnesses* Purpose: To bring health care to rural areas where urban-trained doctors would not settle', 'role': 'assistant'}]