The correct answer is B. Croatia.
Croatia was admitted to the European Union on July 1, 2013, becoming the 28th member state. It is the southernmost country in the former Yugoslavia and is located on the Adriatic Sea. Croatia has a population of over 4 million people and its capital city is Zagreb.
Bulgaria and Romania were admitted to the European Union on January 1, 2007. Cyprus joined the European Union on May 1, 2004.
The European Union is a political and economic union of 27 member states that are located primarily in Europe. The EU operates through a system of supranational institutions and intergovernmental-negotiated decisions by the member states. It aims to bring about the coordination of member states’ economic policies, a single market in which goods and people move freely, and common policies on trade, agriculture, fisheries, and regional development.