Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
we reserve the right to refuse or cancel orders at any time and at our sole discretion . 

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