Answer:
<h2>How others react to you.</h2>
Explanation:
Social health refers to the ability to form relationships and adapt to social situations. So, other reactions to you is important because that way you realise about your social skills.
Obviously, people react negatively to those that lack of social skills, for example, those people that are offensive, not trustful, don't keep secrets, lacking of partnership, and so on... Basically, a non-cooperative behaviour tend to cause a negative reaction on others.
Therefore, if the majority of the people that you tend to meet act negatively to you, it's because you are failing in something, in those cases, you need to evaluate yourself. But, be careful, because this factor is not always against, sometime you're gonna be right.