题目内容：
根据下列材料，回答题：For each blank，choose the best answer from the four choices and write down on the answer sheet. （ 1 ）is a protocol that a host uses to inform a router when it joins or leaves an Internet multicast group. （ 2 ）is an error detection code that most data communication networks use. （ 3 ）is an interior gateway protocol that uses a distance vector algorithm to propagate routing information. （ 4 ）is a transfer mode in which all types of information are organized into fixed form cells on an asynchronous or non-periodic basis over a range of media（ 5 ）is an identifier of a web page.
请回答第（ 1 ）题。
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