Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
content containing commercial activities and/or sales without our prior written consent such as contests , sweepstakes , barter , advertising , and pyramid schemes ; 

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