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: Man doctor at party:  You know , I find this absolutely fascinating . Do you have , uh , an interesting investigation you 've been involved with ? We 'd love to hear about something like that .
Second man doctor at party: Yeah !
Woman Doctor at Party: Yeah !
Columbo: I think that the most interesting investigation is always the _ one _ that you 're working on at the moment .

investigation