How to enforce a blog template in wp-signup.php

Hi

I have created a Blog Template and made it the default. While creating a new site it shows the option SELECT A TEMPLATE and gives a dropdown with my blog template.

I dont want the user to see that option at all. All my users will be using the same blog template and I dont want them to see the dropdown. How can I get rid of this option in wp-signup while enforcing the usage of the default blog template.

Thanks