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: David Rossi:  Victim one gets dropped here .
Derek Morgan: While number two comes around the corner to see what 's happening , and ... the unsub attacks him here .
Emily Prentiss: The female victims were probably here when the first attack occurred .
Derek Morgan: Which means somebody would have to control them pretty quickly .
Emily Prentiss: How many unsubs are you thinking ?
David Rossi: At least one to move the body inside , another _ one _ to take out man number two , and one more to subdue the others .
Emily Prentiss: Well , vandalism breeds a pack mentality .
Derek Morgan: If it is the same unsubs , then yeah , we 're looking at a group of three , maybe four .
David Rossi: These are n't kids . They 're too efficient . There 's control and precision . Juveniles are sloppy .
Emily Prentiss: He 's right . There is nothing tentative about these kills . There 's no experimentation . These guys know what they 're doing .
Derek Morgan: I do n't know ...
David Rossi: What are you thinking ?
Derek Morgan: I can understand vandalism escalating into violence , but that 's usually gradual . An assault , a single murder maybe , but come on , this ? This feel fully evolved .

unsubs