Correct Answer: ​(A), (C), and (D) only. Key Points Environmental determinism is the belief that the environment, most notably its physical factors such as landforms and climate, determines the patterns of human culture and societal development. Environmental determinists believe that ecological, climatic, and geographical factors alone are responsible for human cultures and individual decisions. Although many geographers accepted its central tenants, the concept is most closely associated with the German geographer Friedrich Ratzel and with two Americans who studied under Ratzel, Ellen Churchill Semple, and Ellsworth Huntington. Environmental determinism then became popular in the United States in the early 20th Century when Rätzel’s student, Ellen Churchill Semple, a professor at Clark University in Worchester, Massachusetts, introduced the theory there. Like Rätzel’s initial ideas, Semple’s were also influenced by evolutionary biology. The environment has a critical role in the natural selection process for Darwinian evolution. Environmental determinism rose to its most prominent stage in modern geography beginning in the late 19th Century when it was revived by the German geographer Friedrich Rätzel and became the central theory in the discipline. Rätzel's theory came about following Charles Darwin's Origin of Species in 1859 and was heavily influenced by evolutionary biology and the impact a person’s environment has on their cultural evolution. Additional Information Although environmental determinism is a relatively recent approach to formal geographic study, its origins go back to ancient times. Climatic factors, for example, were used by Strabo, Plato, and Aristotle to explain why the Greeks were so much more developed in the early ages than societies in hotter and colder climates. Ibn Khaldun, an Arab sociologist, and scholar was officially known as one of the first environmental determinists. He lived from 1332 to 1406, during which time he wrote a complete world history and explained that the hot climate of Sub-Saharan Africa caused dark human skin.​