Answer:
Connection between the 2 people
Communication
Being and empath, so understanding each other's needs
Understanding when you're in the wrong
When we are little we see the way our parents or elders act and that tells our brain that is the correct way to act. As we grow up the things they tell us we will become is what we think will happen and so we do that in fear that we will disappoint them.
All equally important without physical health having social health might be harder since you might not be able to interact as well because of illness which would then affect mental. Without mental health your social and physical health would deteriorate and without social health your mental then physical health would deteriorate we need a balanced amount of all of these
