Prefill Checkboxes and send values to backend

[Santhosh sridhar]

Hi, 

I have a multiselect drowdown. I want to display the selected values from a drop-down in a separate div as rows with multiple checkboxes to select.  I have tried this code in JSFiddle, jsfiddle.net/k7nL3s2z . Please let me know if there is any better approach. I need to pass this data(Selected dropdown value with selected checkbox for that row) to backend. Also, the next step would be if Mustard is selected then I need to prefill A,B and C checkboxes already and option to check the rest of the boxes(Will get the list of list of checkboxes to prefill from backend). How to have prefilled checkboxes?

Thanks!