If you need to select multiple controls (checkboxes) you might entertain the idea of giving the controls a specific Tag property. I do not know how many options you have. If there are many options (controls) more elaborate code might be in order.
For instance, if there are a dozen or so options, use the corresponding PK value as the control's Tag property value. Then use VBA to loop through the form's control collection. Have your code identify the Tag property and pass that value to an update or append query.
Here is some air code ...
Code:
dim ctl as control
dim lngPkValue as long
for each ctl in Me.Controls
if len(ctl.tag) > 0 then
lngPkValue = ctl.tag
...
'create logic to do something with PK value
end if
next ctl