I have a B.A. from a good school (and some graduate school work at a great school) but never made it past the ninth grade in high school, nor did I ever get any kind of high-school equivalency. So you can't assume these are always cumulative.
I agree, it's even generally preferred if it's not cumulative, but yeah, click other or click the highest you got to. I guess i should have added "some grad school".