Secondly you apply (or reverse apply) the selections to a cross question.
Build your cross question for APPLY (call this question A):-

and then your question for REVERSE APPLY (call this question B):-

Note that you only need one row, see later.

Thirdly, go back to the first question and insert two filters.
a. If the answer is any of the above APPLY results to question A
b. If the answer is any of the above REVERSE APPLY results to question B

Explanation. When a respondent selects one or more routes then only the selections of those routes are shown in question A. If a respondent omits a route from the selection, then those routes only will be shown in question B.
The easiest way to see this is to set up a simple example for yourself and test it.

Limitation. You use predetermined values to apply to other questions as shown above, that is values from radio buttons, checkboxes and drop down lists. This is because free entry fields cannot be used to drive the filters.

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