is the term for the sum total of perceptions and feelings that an individual has of being a distinct and unique person (a sense of who and what one is).

self

Explanation:

In sociology, George Herbert Mead among others, coined the term "self"-

He noticed how a relative stable vision of ourselves forms , and that we act in relation to that idea of ourselves. He also noticed how this self reacts to social factors, therefore the self is socially constructed , among the many interactions of oneself with the others.

The authors following his works formed the symbolic interactionism

school: his main concept is how the self formed, and how there is always a

"looking glass for the self"  for we imagine how we appear to others and react based on this, as well as we evaluate our actions based on the perceptions of others.

answer; i do believe its (b) 12.5 years of age;