Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
```
( e ) you will not collect usernames and/or email addresses of users for the purpose of sending unsolicited email . 

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