Question: Which war is considered the deadliest and most controversial in world history? 

Context paragraphs:
Bentley Book Prize: The World History Association Bentley Book Prize is an annual literary award given by the World History Association.  It was first awarded in 1999 as the World History Association Book Prize; the name was changed in 2012 to honor Jerry H. Bentley.  The prize is $500.  s of 2013 , five of the winning books had been published by Cambridge University Press.

Glimpses of World History: Glimpses of World History, a book published by Jawaharlal Nehru in 1934, is a panoramic sweep of the history of humankind.  It is a collection of 196 letters on world history written from various prisons in British India between 1930–1933.  The letters were written to his young daughter Indira, and were meant to introduce her to world history.

SAT Subject Test in World History: The SAT Subject Test in World History is the name of a one-hour multiple choice test given on World History by the College Board.  A student chooses to take it depending on a college's entrance requirements.  Until 1994, the SAT Subject Tests were known as Achievement Tests; and from 1995 until January 2005, they were known as SAT IIs.  The SAT World History is not taken frequently.  Less than 17,000 students in 2015 took this test, compared to the over-110,000 students who take the United States History Subject Test.  Also, unlike the other Subject Tests that are administered monthly, this test is only administered twice a year; once in December, and once in June.  This puts pressure on the applicant, because if the student does poorly, it is difficult to retake it.

AP World History: Advanced Placement World History (also known as AP World History, WHAP, AP World or APWH) is a college-level course and examination offered to high school students through the College Board's Advanced Placement Program designed to help students develop a greater understanding of the evolution of global processes and contacts as well as interactions between different types of human society.  The course advances this understanding through a combination of selective factual knowledge and appropriate analytical skills.  Students study all prehistory and history, especially from 8000 BCE to present-day.  The AP World History exam was first administered in 2002.  The course has undergone multiple changes with the latest changes effective Fall 2017.

World history: World history, global history or transnational history (not to be confused with diplomatic or international history) is a field of historical study that emerged as a distinct academic field in the 1980s.  It examines history from a global perspective.  It is not to be confused with comparative history, which, like world history, deals with the history of multiple cultures and nations, but does not do so on a global scale.

World War I casualties: The total number of military and civilian casualties in World War I was more than 41 million: there were over 18 million deaths and 23 million wounded, ranking it among the deadliest conflicts in human history.

Causes of World War I: The causes of World War I remain controversial and debated questions.  The war began in the Balkans in late July 1914 and ended in November 1918, leaving 17 million dead and 20 million wounded.

H. Micheal Tarver: Hollis Micheal Denova Tarver [b. 1958] is an author, historian, and university professor.  He is the immediate-past Editor of the "World History Bulletin" for the World History Association.  Tarver is a former Dean of the College of Arts and Humanities at Arkansas Tech University.  Tarver currently serves as Treasurer of the Southeast World History Association (SEWHA).

Patrick Manning (professor): Patrick Manning (born June 10, 1941) is the Andrew W. Mellon Professor of World History, Emeritus, at the University of Pittsburgh.  He is also president of the World History Network, Inc., a nonprofit corporation fostering research in world history.  A specialist in world history and African history, his current research addresses global historiography, early human history, migration in world history, the African diaspora, and the demography of African slavery.

Jerry H. Bentley: Jerry Harrell Bentley (December 12, 1949 – July 15, 2012) was an American academic and professor of world history professor.  He was a founding editor of the "Journal of World History" since 1990.  He wrote on the cultural history of early modern Europe and on cross-cultural interactions in world history.  He was one of the cited experts in Annenberg Media's 2004 series of educational videos that are broadcast by satellite on the Annenberg Channel.

Supporting paragraphs: Causes of World War I World War I casualties
Answer: World War I