[elwoodblues]

To all those who like prefer option B - Which of the following can be said based on the following:

I went to the store with my brothers, Mark and Ron.


Are Mark and Ron my brothers, or did I go to the store with at least four people?

Written this way: I went to the store with my brothers, Mark, and Ron. It is MUCH more clear and we can omit the comma in cases ONLY in the exceptional case (like where my brothers are named Mark and Ron.)