Russia's leader, czar alexander ii tried to modernize
russian society in the late 19th century. one of his major
accomplishments was ending serfdom, a forced-labor
system similar to slavery. however, alexander ii was
assassinated in 1881, and the czars that followed him
reversed many of his reforms. these leaders were so
harsh that a group of revolutionaries called the bolsheviks
eventually rebelled against them and overthrew the
russian government in 1917.
which statement best describes the main idea of the passage?