Is God an obvious option?

You could imagine that there are four colored balls on a table in front of us, and we are asked to choose one of them. When we choose one of the balls, a believer in God comes and shows us a fifth ball that he has hidden behind his back, gives us a strong blow with a stick in his hand and shouts at us, "Why didn't you choose this ball?"
So how could we choose the fifth ball hidden behind our backs? How could we choose to believe in God, if He is hiding and hiding from us?