Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
tripadvisor operates on a `` notice and takedown '' basis . 

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