premise: There are exactly six computers—P, Q, R, S, T, and U—on a small network. Exactly one of those computers was infected by a virus from outside the network, and that virus was then transmitted between computers on the network. Each computer received the virus exactly once. The following pieces of information concerning the spread of the virus have been established: No computer transmitted the virus to more than two other computers on the network. S transmitted the virus to exactly one other computer on the network. The computer that transmitted the virus to R also transmitted it to S. Either R or T transmitted the virus to Q. Either T or U transmitted the virus to P. Which one of the following could be the computer that was infected from outside the network?
hypothesis: T