1. Jay was at the window. "There go the three Harris girls," he said. "They all look the same to me, always in red or blue." "Eva, Lu and Kim. Nice kids, but they do have a thing about those two colours," Susan told him. "Lu wears blue if, and only if, Eva is in red, and you never see Kim and Eva both in blue. That's Kim or Lu in the red mini, but they wouldn't both wear red." Which of the girls would be in blue that day?

Only Lu wore blue

Only Kim wore blue

Only Eva wore blue