单项选择题
Which layer in the OSI model is responsible for translating frames into bits?（）
A. Application Layer B. Presentation Layer C. Data Link Layer D. Physical Layer
多项选择题 What are three characteristics of UDP?（）
单项选择题 Which simplified IPv6 address is the same as the IP address 2001:0000:1000:0000:0000:cbff:0020:0001/64?（）
单项选择题 What is a valid IPv6 address?（）
