Assuming the italicized clause is <em>Since its establishment, </em>the correct answer here is elliptical clause.
Elliptical means that a word which would normally be part of a sentence is excluded, usually for stylistic reasons. Here, the verb is missing, which is why it is elliptical. The question is oddly formulated too - given that there is no verb here, it cannot be a clause, but rather a phrase, but since there is no such option here, then the correct answer is elliptical clause.
<span>Self-concept
is a social psychology term pertaining to the person’s understanding of
himself, his own existence and how he views himself with others and his
surroundings. To improve one’ self-concept, he needs to know, love yourself and
be truthful to himself. Getting to know on what you really want, what you don’t
want, how you react and think over certain situations is the first step.
Secondly is understanding and accepting oneself and learning to love yourself
no matter how ugly you think you are. And lastly, be truthful to oneself all
the time. If you don’t want to go then don’t go, if you don’t agree then don’t,
be as simple and genuine to what you really feel.</span>
