GRE Reading Comprehension: Kaplan-GRE阅读Kaplan - MN31YN0AS995VGGSG$

Which of the following statements is supported by the passage? A. Vaccination replaced inoculation because it was a safer method of protecting against disease. B. Two random doses of a vaccine are likely to be more similar than two random doses of an inoculum. C. Prior to the 1790s, live virus cultures were often used in tuberculosis inoculations.