Q: In this task, you will use your knowledge about language (and common sense) to determine what element the marked number refers to. The numbers are marked with two underlines around them, like: _ number _. Your answer should be chosen from the given text, and should not contain other words.
Joey Tribbiani: You know how we 're always saying we need a place for the mail ?
Chandler Bing: Yeah ?
Joey Tribbiani: Well , I started building _ one _ . But then I decided to take it to the next step .
Chandler Bing: You 're building a Post Office ?
A:
place