Puzzle- the doors??????!

man wakes up in a room!. sees no windows, a table with a note on it, and 4 doors ahead of him!. each door has a different symbol on its face: rectangle, kite, rhombus, and trapezoid!. he walks to the table and reads the message:
"Three of these doors hold behind them a deadly booby trap, and one of them leads to the exit of this house!. u can only open one door!. the door that leads to the exit of this house can be deduced by looking at a string of numbers hidden somewhere in the house!. figure it out quickly, however, because as soon as the clock strikes noon, all the doors in the house will become permanently locked!."
he then searched everywhere in the room, until he found a string of numbers carved under the table:
1 - 4 - 8 - 11 - 1
He thought long and hard as the clock ticked away, getting closer and closer to his potential doom!.
suddenly he realized what the numbers meant, and promptly went over to the correct door, which he opened and managed to escape ! WHICH DOOR!? and WHY!?Www@Enter-QA@Com

---

---