Hiding the variant selector

Frequently Bought Together can show a variant selector for each product that has available variants. It allows your customers to choose their preferred colour, size, length, etc.

Currently, there is no option in app preference page to hide the variant selector but we can it hide manually. 
However, we don't recommend it. Your customers won't be able to select the variant and the first one will be always selected. They will also lose the ability to select the right variant directly from the widget which may yield lower conversion ratios.
Anyway, if you still want to hide it, just put 
{"display":"none"}

in the 'Advanced options for the product variants'.

To find this section you have to select the Visual preferences section and click on the variant icon in the visual selector to display the style options for the variants.
There you can click on the 'Advanced options for the product variants' link, at the bottom of the section, and type the code inside the text field as you can see below: