L.A.
It can fall into the normal range.. Showering every day is a hassle if she does not want to wash her hair each day.. If she is not very active she may not feel she needs to shower..
It is also not unusual for teens to have favorite clothing that they like to wear so they wear their favorite jeans for many day before being willing to have them washed..
Here is a map of her room or closet..
1. Pile of clothes that have been washed, but not her favorite clothing.. Folded but now covered with books, towels, etc..
2. Pile of clothes she likes ok and has worn 2 or 3 times.. She looks at it holds it up, but does not really want to wear them..
3.Pile of clothing still slightly passable but have worn 4 to 5 day and would make an adult cringe..Easy to wear, looks like what everybody else is wearing.. all broken in..
4. Filthy clothes, probably under the bed (or corner of her closet), that used to be her favorite, but now are too filthy and she does not want to deal with them.. Thus the strange odors in her bedroom or closet..
I am assuming her boyfriend or a female friend will say something if they thinks she has an odor..
If you had a nice talk with her, let it be.. She is old enough to be in charge of her hygiene..
If you are concerned, just keep an eye out for her behaviors, eating well, getting some sleep, can get mildly excited about upcoming events.