Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
if your purchase or use of the services is subject to any type of value-added tax , duty or other governmental tax or fee ( `` taxes '' ) , then we may charge you for those taxes . 

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