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: Captain Jack Harkness:  That 's impossible . I know those ships . They were destroyed .
The Doctor: Obviously they survived .
Lynda: Who did ? Who are they ?
The Doctor: Two hundred ships . More than two thousand on board each _ one _ . That 's just about half a million of them .
Male Programmer: Half a million what ?
The Doctor: Daleks .
Dalek: Alert
Dalek: ! Alert ! We are detected !

ships