Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
parents or legal guardians are responsible for using the parental control functionalities offered by nintendo as part of the nintendo account service if they want to limit their children 's use of nintendo account service . 

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