Final answer:
Bosnia and Herzegovina is the country that lies along the Adriatic Sea between Croatia, Montenegro, and Serbia in the western Balkans. It gained independence following the breakup of the former Yugoslavia in the 1990s and has a complex ethnic composition including Bosniaks, Croats, and Serbs.
Step-by-step explanation:
The country located along the Adriatic Sea, in the western Balkans, between Croatia, Montenegro, and Serbia is Bosnia and Herzegovina.
Following the violent breakup of the former Yugoslavia in the early 1990s, Bosnia and Herzegovina declared its independence in 1992. The region of Herzegovina extends from the city of Mostar to the southern border with Montenegro. The area has a complex history and ethnic composition, which includes Bosniaks (Bosnian Muslims), Croats, and Serbs. The capital city of Bosnia and Herzegovina is Sarajevo.
Tensions following the death of Josip Broz Tito in 1980 between the different ethnic groups, which were largely defined by religious affiliations, led to the dissolution of Yugoslavia. After independence, Bosnia and Herzegovina suffered internal conflict which resulted in the establishment of two entities within the country: the Bosnian/Croat Federation and the Republic of Srpska.