I voted "other".
I've become a big fan of the cotton "shelf style" bras. No wires, no hooks, and the straps don't slide about annoyingly. Not the 50% spandex sports bras - the bras I bought are about 97 % cottton, with just a touch of lycra/spandex. Feels quite like a short fitted tank top layer. Comfy. Gives me that little bit of coverage under lighter weight or knits to avoid most temperature or bright light situations.
I doubt it would completely camouflage when I walk from the 95 degree Atlanta summer day into an air conditioned building, but nothing short of thick fiberfill will do that.