Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
this limited right may be revoked at any time in fitbit 's sole discretion . 

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