RIDDLE HELP!!!! do you know the answer?

[Rowan]

i heard this riddle once, but i never found out the answer, does anyone know the correct answer?
here it is:
you die and then you go to this room. there are 2 doors in this room. one door goes to heaven, and the other door to hell. there are 2 guards in the room, one guarding each door. one guard always lies and one always tells the truth, however you dont know which ones standing infront of which door. you want to go to heaven, and you have one question to ask only one of the guards. what do you ask them?

please help if you know this riddle, its been driving me insane!
thanks!!!!!
remember, you dont know if the truthful guard is standing infront of the door to heavenor not!!!!!!!!
and vice versa.

 

[OMG A YETI]

Ask them are they wearing clothes and if he says no and he is then you'll know lol.

 

[KB24]

I dont know its hard.Ummm ask one of them where the right door is?????

 

[$h4rp$h00t3r]

If you ask the guard on the right door you can immediatly know he's lieing, Why. THEY BOTH LYING, You have to radomly choose a door and hope it's right.