Step 1: Understanding the Book.
'An Essay on the Principle of Population' (1798) was written by Thomas Robert Malthus. It is a foundational work in the study of population dynamics and economics, where Malthus argued that population growth would outpace food production, leading to famine and hardship unless controlled.
Step 2: Analysis of the Author.
Thomas Robert Malthus, an English economist and demographer, is best known for his theories on population growth and its implications for society. His work had a profound impact on economics and sociology.
Step 3: Comparison with other options.
- (A) Thomas Robert Malthus: Correct. Malthus wrote 'An Essay on the Principle of Population' in 1798.
- (B) Adam Smith: Incorrect. Smith is known for his work 'The Wealth of Nations,' not for this essay on population.
- (C) Emile Durkheim: Incorrect. Durkheim was a French sociologist and did not write this work on population.
- (D) Karl Marx: Incorrect. Marx is known for his works on socialism and communism, not for population studies.
Step 4: Conclusion.
Based on the historical context and content of the book, the correct author of 'An Essay on the Principle of Population' (1798) is Thomas Robert Malthus.
Final Answer:} Thomas Robert Malthus.