Web UI for categorizing a list of items

I have a web page that displays a list of 100+ items (where each item is a row containing an image plus some metadata) that I would like the user to categorize into "A" or "B" or neither but not both.

I thought about using radio buttons on each row since that enforces the "not both" requirement but the problem is radio buttons can't be unselected. One workaround would be to make "None" a third radio button.

Another way is a dropdown, which would also require a "None" option.

The last way I could think of are 2 checkboxes that use javascript to enforce the "but not both" requirement. Since checkboxes can be unchecked, this method allows for the "None" option.

Would like to hear thoughts on which is the best option either from above or something different.