According to the passage, scientists have discovered that influenza viruses ____

游客2024-06-30  10

问题 According to the passage, scientists have discovered that influenza viruses ______ . [br] New strains of viruses are transmitted to man by ______ .

选项 A、A type of wild pig
B、diseased lower animals
C、a group of migrating birds
D、a variety of means

答案 D

解析
转载请注明原文地址:https://tihaiku.com/zcyy/3657341.html
最新回复(0)