Since cyan means 50% green and 50% blue, other than exactly in the middle of the chart, all the colors shown are either to the left of cyan(the middle), or to the right. So all the colors are either slightly to a lot blue or slightly to a lot green. This test is testing where everyone middle essentially is. If there were as cyan/turqouise option, that would be a very different test, I imagine essentially testing to lines, where the line between blue and cyan/ambiguity begins and the line between green and cyan/ambiguity begins requiring I imagine several more questions to get that answer and would only then be showing two lines on the graph, vs this test which is able to say if you lean more to the right or left of the middle of blue to green.
