For each blank, choose the best answer from the four choices and write down on the answer sheet. (66)is a protocol that a host uses to inform. a router when it joins or leaves an Internet multicast group. (67)is an error detection code that most data communication networks use. (68)is an interior gateway protocol that uses a distance vector algorithm to propagate routing information. (69)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. (70)is an identifier of a web page.