Thanks for the reply.
They are standard DNN Links modules set as Control Type: Dropdown & List Format: Vertical.
I think the problem would go away if, after I hit the "Back" button and return to the page with the Links dropdowns, the one which was previously selected would reset to the "selected" option. That's what is occurring in IE. In the other browsers (at least Chrome & Firefox) , the previous selection persists in the dropdown when I go "back" to the original page.
But sounds like a more solid fix would have to do with which method is associated with each list, as you suggest.
Here's a link to a page exhibiting this problem. Those three dropdowns in the upper right. The behavior is a bit inconsistent: It appears that the top list is the main offender - when that one is selected first, and the page is returned to, and then one of the others is selected, the selection from the top list still displays (again, in Chrome & Firefox).
Thanks and let me know if I can explain better.