Question: What is the three letter abbreviation for the country, which maintains border troops, that claims Bernd Baumgart as a citizen?

Knowledge 1: Bernd Baumgart
Bernd Baumgart (born 3 July 1955) is a German rower who competed for East Germany in the 1976 Summer Olympics. [SEP] Knowledge 2: Literature of East Germany
East German literature is the literature produced in East Germany from the time of the Soviet occupation in 1945 until the end of the communist government in 1990. The literature of this period was heavily influenced by the concepts of socialist realism and controlled by the communist government. As a result, the literature of the German Democratic Republic (East Germany) was for decades dismissed as nothing more than "Boy meet Tractor literature", but its study is now considered a legitimate field. Because of its language, the literature is more accessible to western scholars and is considered to be one of the most reliable, if not the most reliable, sources about East Germany. [SEP] Knowledge 3: North Korea
North Korea (Korean: ; MR: "Chosŏn" or literally ; MR: "Pukchosŏn"), officially the Democratic People's Republic of Korea (DPRK or DPR Korea; Korean: , "Chosŏn Minjujuŭi Inmin Konghwaguk"), is a country in East Asia constituting the northern part of the Korean Peninsula, with Pyongyang the capital and the largest city in the country. To the north and northwest, the country is bordered by China and by Russia along the Amnok (known as the Yalu in Chinese) and Tumen rivers and to the south it is bordered by South Korea, with the heavily fortified Korean Demilitarized Zone (DMZ) separating the two. Nevertheless, North Korea, like its southern counterpart, claims to be the legitimate government of the entire peninsula and adjacent islands.
Knowledge 1: Bernd Baumgart
Bernd Baumgart (born 3 July 1955) is a German rower who competed for East Germany in the 1976 Summer Olympics. [SEP] Knowledge 2: Literature of East Germany
East German literature is the literature produced in East Germany from the time of the Soviet occupation in 1945 until the end of the communist government in 1990. The literature of this period was heavily influenced by the concepts of socialist realism and controlled by the communist government. As a result, the literature of the German Democratic Republic (East Germany) was for decades dismissed as nothing more than "Boy meet Tractor literature", but its study is now considered a legitimate field. Because of its language, the literature is more accessible to western scholars and is considered to be one of the most reliable, if not the most reliable, sources about East Germany. [SEP] Knowledge 3: Edmund Burke
In January 1790, Burke read Dr. Richard Price's sermon of 4 November 1789 entitled, A Discourse on the Love of our Country, to the Revolution Society. That society had been founded to commemorate the Glorious Revolution of 1688. In this sermon Price espoused the philosophy of universal "Rights of Men". Price argued that love of our country "does not imply any conviction of the superior value of it to other countries, or any particular preference of its laws and constitution of government". Instead, Price asserted that Englishmen should see themselves "more as citizens of the world than as members of any particular community".
Knowledge 1: Literature of East Germany
East German literature is the literature produced in East Germany from the time of the Soviet occupation in 1945 until the end of the communist government in 1990. The literature of this period was heavily influenced by the concepts of socialist realism and controlled by the communist government. As a result, the literature of the German Democratic Republic (East Germany) was for decades dismissed as nothing more than "Boy meet Tractor literature", but its study is now considered a legitimate field. Because of its language, the literature is more accessible to western scholars and is considered to be one of the most reliable, if not the most reliable, sources about East Germany. [SEP] Knowledge 2: Heinz-Josef Große
Heinz-Josef Große was a 34-year-old East German (GDR) construction worker who was shot and killed on 29 March 1982 by GDR border guards on the Inner German border at Schifflersgrund, near Bad Sooden-Allendorf. [SEP] Knowledge 3: Bernd Baumgart
Bernd Baumgart (born 3 July 1955) is a German rower who competed for East Germany in the 1976 Summer Olympics.

Answer: GDR