How do I get rid of other themes

How do I get rid off other themes such as ALT, EVO, UNI so that users don't get to select these themes but just stick to the one theme I provide..

1. Go to Admin/Settings/Templates

2. Click Settings on the top right

3. Choose your default template

4. Untick Allow Users to Choose Template

5. Save

You may wish to clear the Cache.

This will remove Template option from the bottom menu.

You can delete the EVO template but I wouldn't bother. The others are needed.

Thankyou