What are Four's fears in his fear landscape?

Four invites Tris into his fear landscape. Before they go in, he tells her to see if she can figure out why they call him Four, and if she can figure out his real name. In the first part of the landscape they're on top of a building, reflecting his fear of heights, and they have to jump off. Next they're trapped inside a small room, representing his fear of confinement, and they have to scrunch up tight in order to pass this stage. They're closer than they've ever been, both physically and emotionally, and Tris makes him talk about the origin of this fear. Four tells her he was punished as a child by being forced into the small upstairs closet. Next, a woman is pointing a gun at them, and on a table next to them is another gun; Four must kill her.

Then finally, he has to face a man that Tris recognizes: Marcus Eaton, one of the Abnegation representatives. She realizes that Four is really Tobias Eaton, the boy who transferred to Dauntless. Marcus begins to beat Four - now Tobias - with a belt, and Tris steps in its path. She grabs the belt and swings it towards Marcus instead. Then the landscape ends, and Tris realizes that he only has four fears: that's why they call him Four.

thank u

i have no idea