which of the following is true select one: a. the plan for this computer network (to be called arpanet) was presented in october 1967, and in december 1969 the first three-computer network was up and running. b. the plan for this computer network (to be called arpanet) was presented in october 1967, and in december 1969 the first five-computer network was up and running. c. the plan for this computer network (to be called arpanet) was presented in october 1968, and in december 1969 the first four-computer network was up and running. d. the plan for this computer network (to be called arpanet) was presented in october 1967, and in december 1969 the first four-computer network was up and running.