Hello everyone. I provide templates for Microsoft word at my site (https://www.docformats.com/) and i am planning to sell few categories, for example award certificate templates, baby shower invitations etc.. I am professional with MS Office but confused at which image extension will work perfectly at background with whom printing results should be high quality. Of course it also depends on printer being used for printing but i want to make sure that my template is good enough for commercial printing.

P.S i do also provide background design of size 3200px along with template.