<em>My older brother was my hero when I was growing up</em>. This is the correct option. The writer is setting the focus on one fact. He/ She thinks this fact is emotionally important and this emotional view is reflected through the words" my hero". Besides, the speaker is talking about his / her brother.
These options are not right:
-When I was young I was the smallest one in my class. This may belong to an autophiography because the writer refers to a specific time in his/ her life: "When I was..." and the information he / she gives is objective.
-Daniel hit the ball so hard it flew out of the park. This refers to a third person and the link between this person and the writer is not given.
-Natalie’s family went to the seashore every year. The same as avobe.
Richness in the appearance of both the knight and his horse, the description of his horse as "monstrous", the statement that no man as mighty as the Green Knight has ever been known before.
