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.

Example Input: Captain Kathryn Janeway:  You 're not suggesting we wait until this ... Chaotica defeats the aliens ?
Tom Paris: No , no . I 'm suggesting , that we help the aliens to defeat Chaotica . They think he 's leading some kind of hostile invasion force , once that threat is gone it 's a good bet they will leave and close up their portals .
Chakotay: How do you propose to defeat Chaotica ?
Tom Paris: Well , he 's been attacking the aliens with his Death Ray ...
Tuvok: It 's a shame we do n't have _ one _ .
Tom Paris: No , forget about what it 's called Tuvok ! In the world of Captain Proton it 's the most powerful weapon that there is , and because it 's photonic it 's lethal to these aliens . Now , in chapter 18 Captain Proton disables this weapon Just before Chaotica can use it to destroy Earth .
Captain Kathryn Janeway: And you think that Proton - namely you , of course - could still do that ?
Tom Paris: Well , we 'd have to knock out the Lightning Shield first ...
Seven of Nine: A force - field .
Tom Paris: Yep , now you 're catching on . The Destruct - o Beam on my Rocket Ship can can disable the Death Ray but only if someone gets inside the Fortress of Doom and can shut down the Lightning Shield .
Example Output: Ray

Example Input: Donald Davenport:  Do n't worry . I promise I will get Adam the safest car available .
Chase Davenport: The safest car is the _ one _ he is n't driving .
Example Output: car

Example Input: Leonard Hofstadter:  Let me ask you something : do you think it 's okay for Penny to have an ex - boyfriend sleep on her couch ?
Howard Wolowitz: No , I mean she 's obviously way out of line ...
Leonard Hofstadter: Thank you .
Howard Wolowitz: But if she dumps you , she 'll have a new boyfriend by tomorrow morning , and you 'll have a new girlfriend when you figure out how to build _ one _ .
Example Output:
girlfriend