Can't Pre-select two answer options

Hi there,



I have two questions - Q9 and Q17.





If I select Q9 = Canberra Centre (Q9 = 5) and Q9 = At the Game master’s exhibition (Q9 = 4), then the options in Q17 which are Q17 = 1 and Q17 = 14 should be pre-selected.



So _Q9 = Canberra Centre_ –> _Q17 = 14_ should be selected.

_Q9 = At the Game master’s exhibition_ –> _Q17 = 1_ should be selected.





For both these options, If I select single option, then the option in Q17 is selected but If I select both, none of the options are selected.



Here is my Javascript code:

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