the multiple response option turns comma delimited lists of strings in a cell into individual levels.
In your case it looks like you have only two levels in the column being filtered, its either missing or "selected"
If you had levels that were, for example
cat, dog, bird
dog, bird, cat
bird, cat, dog
These would be read as three separate levels eventhoug all three contain the same three items
multiple response would see them as one level, each with the same items.
it has a pretty big impact on the way filters work
JMP Systems Engineer, Health and Life Sciences (Pharma)