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 . 

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