What happens next in this paragraph?

A boy is seated at a table in a crowded room. He has a rubik's cube, and tries to solve the puzzle. he
Pick your answer from:
[I] opens and closes his mouth until he come to a conclusion..
[II] solves all of the rubiks cubes in less than ten minutes with the help of a teacher..
[III] times himself as he finishes the cube, tossing it down on the table..
[IV] tries again, and is shown this time attempting a landing goal, knocking down a longer than normal cube..
[III]