Exempt Dividend interest on Illinois state return

I received dividends from an investment account and I have some exempt interest in my 1099-DIV(box 11). I know the amount of in-state and out of state income included in Box 11 of my 1099-DIV.  I am trying to answer this question presented by Turbo Tax while filling up my IL - State return

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After clicking continue in this screen, I am taken to this screen

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all I know is my exempt interest is from a national municipal bond mutual fund. What should I select in the screen above and what portion of my exempt interest is taxable in IL?