Remove or make a default selection for variant dropdown menu

On my website, there's to options for variants. The issue I'm having is when a customer comes to my website and see the product page, the variant images aren't shown unless the customer makes a selection in both variant options. This makes it more difficult for the customer to see which variant is labelled with the name of the variant.

Is there a way to make a default selection for the variant dropdown menus, so that when a customer arrives at the page, a selection is already made for each variant option? Or maybe even a way to remove the "Select Color" option of the dropdown menu, so it just shows one of the colors right away?

There has to be a way to use the code injection function to do this. Anybody have any tips?