Due to the last hint, we can analyze the situation.
A) Wait for the Tank – Logically, best answer because it’s stupid. Even with an army, a Tank is still overkill. I’m assuming some crap happens to the Tank. 😉
B) Wait for the Helicopter – Obviously not the brightest idea – if we wait for the Helicopter, it would attract more zombies, probably owning us all.
C) Go down the Emergency Exit – Best choice, but due to Arly’s suggestion…
I’m going with A.
I hope you aren’t biased. You should pre-write the ideas, which I think you did, so. 🙂