Add new option to Stacked dropdown

Hi, we were wondering if we could add a new option to the Stacked composite dropdown, that we want would be a new option saying “Without $x”, right now there is the default option saying “Select your $x” and the other options to select the component, but we would like to add a new option saying “Without $x” so the customer also has the option to not select a component, is this possible?

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