单选题 TCP (Transmission Control Protocol) was specifically designed to provide a reliable end-to-end byte stream over a(n)______.
A．IP address B．reliable network
C．socket D．unreliable internet work

【正确答案】 D
【答案解析】[解析] 本题的含义是，TCP被设计用于在不可靠的互联网上提供可靠的端对端，选择答案D正确。