Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
the transfer of virtual items and merchandise is prohibited except where expressly authorized in the service . 

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