Read the passage below and answer the questions that follow:-

Arun was an intelligent smart and friendly boy who was very popular amongst his peers. He often did not carry his lunch box to school but would eat from his classmates tiffins, on the sly, under the pretext of checking their bags for bringing mobile phones. He would often regret his behaviour at home but was unable to resist his temptation for interesting food and a little prank. On one such day Arun founds Rs. 500/- in a friend's bag. Although he was tempted to take the money to buy food from the canteen, he did not take it, as he understood very well that it would be going too far. Stealing was something his conscience would never allow.

Which structure of personality works on the 'reality principle'?

Ego

Ego : It grows out of id, and seeks to satisfy an individual’s instinctual needs in accordance with reality. It works by the reality principle, and often directs the id towards more appropriate ways of behaving. For example, the id of a boy, who wants an ice-cream cone, tells him to grab the cone and eat it. His ego tells him that if he grabs the cone without asking, he may be punished. Working on the reality principle, the boy knows that the best way to achieve gratification is to ask for permission to eat the cone. Thus, while the id is demanding, unrealistic and works according to pleasure principle, the ego is patient, reasonable, and works by the reality principle.