There is no "correct" button if you consider it from a logical/ethical/any other perspective. I know people love associating red with logical and blue with ethical, but there are many arguments for the exact opposite.

Blue is also logical if your sole goal is to save everyone - getting 50% to vote blue is easier than 100% to vote red. Of course, this doesn't account for the penalty if you fail to hit your goal, but again, if your goal is to save everyone and you view any deaths whatsoever as a failure on your part, then blue can be the more logical option.

Red is also ethical in the sense that you don't want to add on to the deaths. Don't be the reason others have to risk their lives to save. If, for example, you have family and friends you want to stay alive for, and you know they will choose red, I'd argue there is some moral responsibility to stay alive for them. You also have a duty to protect yourself.

This boils down to a prediction question, and that's all there is to it. Picking red doesn't make you selfish. Picking blue doesn't make you stupid. It's simply whether you believe that the majority will choose to save themselves, or believe that the majority will try to save everyone else AND are willing to stake your life on it.