It would be very useful if you could block certain choices when a particular choice is selected in one select_multiple.
For example, if you have the following question 'bat evidence seen' with the options - none; droppings; bats visible; bats audible. it would be very useful if 'none' was the selected then you cold not select any other options.
This could be done by using two questions, is there any evidence - yes/no and what evidence was seen. however, it would be much slicker with just one question
