Context: As we pressed our faces to the windows to look at the yard , I could n't help but wonder why we would need a key to unlock a door from the inside .
Question: What may be the reason a key was needed to unlock the door .
Option 0: It was a security feature to prevent them from sneaking out .
Option 1: It was a way to remind the owner to always have their house keys .
Option 2: It was a mistake made by the person who installed the door .
Option 3: It was a way to play a prank on guests trying to leave the house .
Answer: 0