Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
persons under the age of 13 , or the equivalent minimum age in the relevant jurisdiction , are not permitted to access or use the fitbit service unless their parent has consented in accordance with applicable law . 

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