You can add conditional logic only to our Virtual Options. You cant do this with Shopify Options because Shopify Options are always required.
To add conditional logic make or edit a Virtual Option.
Check the box for conditional and it will only show this option if a defined option is selected.
In this example, the product option I just created will only appear when Size Small is selected.
You can only apply one value for conditional logic, and each new virtual option needs to have a unique title.