147012
The security features governing the security of an identity can be divided into three levels of security , i.e. Level 1 Security ( L1S ) ( Overt ) , Level 2 Security ( L2S ) ( Covert ) and Level 3 Security ( L3S ) ( Forensic ) .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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