Rn board exam. Where to take it.?

I am in th army and my wife is an lvn that graduates her rn in may. She just started her clinicals last week. After she graduates she has to take the rn nursing bar. The thing is we are ststioned in texas and will be moving to eashington dc in july. We are under the impression that she has to take the texas exam because her online nursing program and clinicals are in texas. I am sure she eill do fine but worst case scrnario she does not pass the board exam and hss to eait to take the test again in which we will be relocated to washington dc. Is there a way she can take th test in dc or will she have to take it in texas? If sje has to take it in texas can it be anyehere in texas or a sprcific exam center?