Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
we reserve the right , but not the obligation , to monitor or become involved in disputes between you and other users . 

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