If she's in college and planning to use it for short trips, she wants something pretty cheap (used) because it might get stolen, even with a good U lock. A rack will make it a lot easier to get around and carry or pick up stuff. For short trips, it doesn't have to be very comfortable, you don't really have time to get uncomfortable. If she wants to also go mountain biking or longer road rides, a nicer more comfortable bike stored inside is good, but never park it on campus or on the porch in student housing neighborhoods.
2009 Trek 7.2FX WSD, brooks Champion Flyer S, commuter bike