Definition: 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.
Input: Sergeant Frederic Wilson:  J'ever see one of these before , Lieutenant ?
Columbo: Uh ... no , not sure I have . It , eh , looks kind of familiar , though .
Sergeant Frederic Wilson: It 's a camera - mounted starlight scope . They used 'em quite a bit at Berkeley for night work .
Columbo: You mean that takes pictures in the dark ?
Sergeant Frederic Wilson: Yeah . I bought this _ one _ myself .
Columbo: You used your own money ?
Sergeant Frederic Wilson: Well , I wanted to have the best equipment for the job , sir .
Columbo: You must be a bachelor .

scope