The correct answer is D. It shows colleges that you have what it takes to excel at their school.
There are many extracurricular activities that can give you extra ECTS points based on the education frame found commonly in Europe and some other places. Also, you do get a chance to help people and develop new skills. This however does not mean that you'll be great at a college. If you participate in a "clean your college day" activity, that doesn't mean that you'll excel at Harvard if you choose to go there.