What I'd think: Oh crap, I'm probably dying tonight. ah well. better go out with a bang >= D

What I'd say: I was wondering when you'd stop hiding...

I chose "Scream and run for saftey" though I probably wouldn't scream. I would just run. Either that or ask who it is.

TURRIFYIN!

From experience I think I know how I'd react. This sort of thing has happened to me once or twice. (I have annoying friends who like to scare their friends.)

I always attack. (But that was because the wicked whisper or, in the other case, the attacking roar, was RIGHT BESIDE MY HEAD. NO TIME TO RUN.)

Whether or not that is a good idea depends on what the attacker turns out to be. In my case, of course, I just ended up hitting my friend.

THERE'S NO OPTION FOR "JUST STAND THERE BECAUSE YOUR WHOLE BODY WENT NUMB".
As is what generally happens to me when I get really scared.
But I picked "Ask who it is."

I'd ask who it is, but I already have and idea who...*whispers*she wants to kill me.

...*cough*Amber*cough*

I would probably turn slowly towards the voice and ask them what they wanted. I don't scare easily, but the dark definitely makes me a bit wibbly in the knees.
So if I got no answer I would shrug like I didn't care and walk away whistling.
Or maybe singing...it confuses things when you pretend you don't care...
^^ Always gotta outfox the fox.

I need no stick. I have a flamethrower. I'd go after that 'voice' with it. >U>

If it´d be a sexy voice I think I´d shiver xD
If not, I´d go away

I guess I wouldn't scream... I sort of do the whole Freeze-in-alarm-then-creep-away-slowly-and-as-quietly-as-possible-before-breaking-into-mad-Jack-Sparrow-run-instead.

-Thumbs up.

i'd ask who is... running! XD

well, i'd like sooo much to fight like a brave knight/ninja/warrior, but sadly i'm not used to carry a sword or something like that with me... most of times

oh, but i have the pepper-spry! better than nothing, i suppose...