Did you scroll down to make sure that the answer wasn't off the screen? If you really think a question didn't have the right answer then you need to study more. I doubt that any of the questions have such a basic flaw.
As far as the test went....do they make it harder? Although my scores were about the same, today's test had quite a few questions where the correct answer just wasn't there. Without going into details, there was a question about (equals & ==) & a question about overloading that just didn't have the right answer.