I believe that the events that tirggered the breakup of Yugoslavia were two of the options given, firstly the death of Josep Tito and the collapse of communism in Eastern Europe.
After the allied victory in World War II Yugoslavia was set up as a federation of six socialists republics; Boznia and Herzegovina, Croatia, Macedonia, Montenegro, Serbia and Slovenia. There were also two autonomous provinces that were established within Serbia; Vojvodina and Kosovo. Each of the republics had its own branch of the League of Communist of Yugoslavia party and any tension were solved on the federal level.
The yugoslav state model of organization and a sort of middle way between planned and liberal economy had been a success and the country experienced a time of strong economic growth and political stability under the rule of the president for life Josep Broz Tito from 1960 to 1980. But after Tito´s death on 1980 Yugoslavia left what the international political observers saw as the main unifying force. Ethnical nationalism began to rise and together with the weakening of the communist states in Eastern Europe lead the country into a crisis that the official leading pary, the League of Communist of Yoguslavia, could not solve.
With the collapse of the communism represented by the fall of the Berlin Wall in 1989 the crisis deepened and from 1991 the country began to disintegrate along its ethnic lines.
From the options given I think that the correct answers are those I picked out because the rest of the options given happened during the 1990 decade and are a result of the breakup of Yugoslavia. But the death of Tito and the collapse of communism are the ones that triggered the breakup.
Hope this answer help you. Regards.