Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
the failure of crowdtangle to exercise or enforce any right or provision of the terms of service shall not constitute a waiver of such right or provision . 

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