The correct answer is option 2: Greece. In the year 2015, Greece faced a severe economic crisis that resulted in a default in the repayment of a loan to the International Monetary Fund (IMF).

Greece`s economic crisis, which began in 2009, was characterized by factors such as high levels of government debt, a significant budget deficit, and a struggling economy. The country`s debt burden became unsustainable, leading to the need for financial assistance from international institutions such as the IMF.

In 2015, Greece was unable to meet its repayment obligations to the IMF and became the first developed country to default on an IMF loan. This default had significant repercussions for the Greek economy and the stability of the Eurozone as a whole.

It is important to note that while China, Ireland, and Belgium are all nations that have their own unique economic challenges, they were not the nations that faced severe economic crisis resulting in defaulting on an IMF loan in 2015.