Select list item: List index too large ::: How to fix

The error is probably in the highlighted area in the picture I have attached

Your list after selection i.e variable Q has only 1 element. and what you have done in
set Chioce1.Text to selection from list Q , that too with Index (in your case 3) which is greater than the length of the list which is just 1

the error does not end here as the further blocks (within the highlighted area) have the same issue. So check those as well!