The correct answer is (c) Dudley Stamp.
Dudley Stamp (1898-1966) was a British geographer who is best known for his work on agricultural regions. In 1936, he published a book called “The Land of Britain: Its Use and Misuse”, which classified the world into agricultural regions based on their climate, soil, and vegetation. His work was influential in the development of agricultural geography and is still used today.
(a) Whittlesey was an American geographer who is best known for his work on political geography. He published a book called “The Earth and the State: A Study of Political Geography” in 1939.
(b) Helbern was a German geographer who is best known for his work on regional planning. He published a book called “Die räumliche Ordnung der Wirtschaft” in 1949.
(d) Hartshorne was an American geographer who is best known for his work on the philosophy of geography. He published a book called “The Nature of Geography” in 1939.