Interesting question. As a data scientist I'm forced to say Man - Purely because, a probably higher than I'd like to admit proportion of men will be rapsits/predators/killers, but you could bump into my brother out for a walk or one of our sons doing a scout hike etc etc, whearas pretty much every bear, unless it's just eaten, is going to try and kill and eat you. So statistically, I'd take my chances with a man (and I know where the weak spots are, could have a go at a kick in the bollocks that might buy me enough time to get away etc).
However, PP is exactly right. I hear many parents, mothers and fathers, and I have said to my own children, if you get lost find a woman and ask her for help. If someone is hassling you on the train, go and sit with a woman. No one says go and find a man.