Feed selection in Contact form plugin

Hi! I have a question regarding the Contact form 7 plugin. I use it on a website I made and I would like to add a selection box in the contact form. In this selection box I would like to display all the products I uploaded in a so-called ‘assortment-page’. Does anyone know how to do this? Website is http://www.smaakenco.nl

Thanks in advance!

Koen

https://wordpress.org/plugins/contact-form-7/