单项选择题What is not the surprising purpose of travel according to the author? A、Experiencingmulticultural contrasts. B、Mental flexibility. C、Open-mindedness. D、Relaxation.
单项选择题甲型肝炎病毒的主要传播途径为 A. 输血 B. 粪-口 C. 注射 D. 昆虫媒介 E. 母婴垂直
