How to Concatenate cells separated by comma when adjacent cell is checked (or is there an easier way without the checkbox?)

Question

Here is what I'm working with and what it should look like:

When a category is checked on the right side of the image, cell B12 should concatenate those cells together and separate each entry with a comma. I think I'm pretty good with formulas but this is a little beyond my skill level and nothing I'm doing is working.

Answer 1

You may try:

=join(", ",filter({D:D;F:F},{E:E;G:G}))