Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
it is fitbit 's policy , in appropriate circumstances and at our discretion , to disable or terminate the accounts of users who repeatedly infringe the rights of copyright holders . 

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. OPTIONS: ['Limitation of liability' 'Choice of law' 'Unilateral change' 'None'
 'Unilateral termination' 'Contract by using' 'Arbitration'
 'Content removal' 'Jurisdiction'].