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: Katara:  Why would you even try to defend him ?
Toph: Because , Katara , you 're all ignoring one crucial fact ... Aang needs a Firebending teacher . We ca n't think of a single person in the world to do the job . Now _ one _ shows up on a silver platter and you wo n't even think about ?
Aang: I 'm not having Zuko as a teacher .
Sokka: You 're darn right you 're not , buddy .
Katara: Well , I guess that 's settled .
Toph: I 'm beginning to wonder who 's really the blind one around here .

teacher