if you have the room just grow them all. you may not even get a female out of any of those 3. It will be good to learn from the early growth too. This is my first run from seed and got 3 sprouts from 4 seeds. One was female for sure so I waited a week after i spotted that one then killed the other 2. I am wishing now I hadn't done that and just grew her for seed to learn and get more seeds. Now I am starting over and going to make a seperate veg room while this one finishes. Then seed a female(took a clone off the female I am flowering now), so at least one female to seed. Anyways im baked right now but I would just grow what you have your first time to learn and practice.