Read the passage from "Stalin: A Brutal Legacy Uncovered,” which is an informational text about Stalin’s atrocities and how he used ambition and fear to rule over people of the Soviet Union. Stalin's genocidal record was the product of a ruthless, steely personality hardened by searing hardships in his youth: first, brutal beatings by his alcoholic, dirt-poor father; and later, several rounds of imprisonment and exile—from which he often escaped—following his expulsion from a Russian Orthodox seminary for fomenting a strike of railroad workers. For the 20-year-old Stalin, an outstanding student with top marks in Bible and Church studies, the strike was the first step on a new road—a career of rebellion, crime, and radical politics that eventually made him the unquestioned boss of the Communist Party and of 140 million people in the Soviet Union.

Which text structure is used in this passage?

cause-effect
sequence
problem-solution
comparison-contrast