My father was in the Israeli Army in the late fifties all the way through the early sixties (he even got called up for reserve duty in '67). In the army, a very important drill was the "walk to the next town over carrying a backpack full of shit" drill, and there were two kinds of packs that were used. There was the light pack, and then there was the so-called "elephant pack". The drill sergeants, thick as they were, would often just say "take a pack and go to the next town". And always, there was one idiot or another who would ask the question: "which packs?" The answer was ALWAYS "the elephant packs". The moral of this story is simple and obvious: when presented with ambiguous instructions, shut your trap and pick the one that suits you better. If they tell you that you did the wrong way, you have the ambiguous instructions on your side. They just said "take a pack" - and by golly, I did!
Even stupider is asking when the instructions are unusual, but clear and in your favor. Just follow the instructions, don't ask if they're what your commanding officer/boss/professor really meant to ask. On this note, to the guy who just asked my professor if the homework was really due Thursday rather than tomorrow: you are an idiot (and you know who you are). It said Thursday, just turn the fucking homework in on Thursday! Now I have to pull an all-nighter, thanks to your goody-two-shoes questions. It's as if they said "take a light pack and head north" and you responded "are you SURE you didn't want us to take the elephant packs?", at which point they said "oh, you're right, drop the light packs and shoulder those fucking elephant packs!"
Just STFU and go with the easy, moron!