That depends. It’s going to take 20 years of constant training to get her ready to go to Mars, so starting her out at 17 is a good age.
As long as there are no illusions about what needs to be done, I’m fine with this.
That was akin to my thought. Such a mission will be, likely, the entire body of work of a lifetime for whoever. I wish the young lady luck.
With a proper vehicle, with centrifugal gravity, even an overweight and out-of-shape person could go to Mars.
If we had a propulsion system capable of sustained thrust you would not even have to endure the high-G of launch...we will get there.