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: Stan:  All right . Will you donate one of your kidneys to Kyle ?
Cartman: No no no no no , no no no no no ...
Stan: You only need _ one _ , fat boy !
Cartman: ... no no no no no no no no no no no ...
Stan: Dude , one of your friends is gon na die . Do n't you see how serious this is ?
Cartman: HEY ! THAT SON OF A BITCH ! Okay , asshole , give me back my kidney !
Stan: Dude , please , Kyle needs it !
Cartman: It 's mine ! Not yours , mine ! Give it back right now or there 's gon na be hell to pay !

kidneys