Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
you also acknowledge that these terms and the fitbit privacy policy do not apply to any third-party services . 

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