AlpineR:The series consists of patterns with reflectional symmetery about the diagonal, except with green on one side and blue on the other. Two of the answers follow that pattern, but one has already appeared. The answer is the other.
There may be a WTF in there somewhere, but the lack of a correct answer is not it.
I saw that too, and it's not surprising that programmers, thinking sequentially, would mix it up. However, IQ tests aren't supposed to be trick questions, and you have to admit that the arrangement of images definitively implies a sequence (hell, they even call it a "series" as opposed to something non-sequential like a "set"). So either the question (a) is deliberately misleading, (b) is poorly-worded, or (c) was actually a mistake, and has a reasonable answer only by coincidence.
I'm actually leaning toward option (c), because if the common property of the "series" is symmetry about the diagonal, then the 3rd option does not actually make the series "complete". The symmetry may simply be an incidental side-effect of the rotational transform - if you start with a reflection and rotate both sides around the center of the reflected axis, you will always have symmetry.
No doubt if you put that question in front of me I'd have made the same call that you did, but I don't believe that you'd ever see that kind of a question on a real IQ test. I believe that they messed it up, even though it does have a viable answer.