To girls, how many of you have six-pack abs?
I certainly don't. :)
There are women who have a six-pack, but it's a lower percentage than that of men.
The problem is that, whether or not you have a six-pack is about your body fat percentage more than anything else. It's not really about "strength" or whatever. Figure, everyone has those muscles. The question is whether they show, and that depends on how much subcutaneous fat is layered on top of them. You need to have a pretty low body fat percentage - usually down into the single digits - to have visible abdominal muscles.
Women naturally carry a bit more fat on our bodies than men do. We need the extra fat for reproductive functions; a female athlete who works and diets her fat percentage down too low can stop having a period, for example. Our bodies want to maintain a bit more fat so we have the extra resources to support a pregnancy. This is in our DNA; there's nothing we can do to change that tendency.
It's possible for a woman to get her body fat down low enough to show her abs, but she has to work a lot harder for it than a man would. Most women don't think it's worth the effort.