Option 1: 1919 -> This year is too late and corresponds to the post-World War I period.
Option 2: 1775 -> This is one year before the actual publication date.
Option 3: 1776 -> This is the year Adam Smith's seminal work was published.
Option 4: 1936 -> This year is far too late and corresponds to the Great Depression era.
Hence, Option 3: 1776 -> 'An Enquiry into the Nature and Causes of the Wealth of Nations' was published by Adam Smith in 1776, the same year as the American Declaration of Independence. This foundational text of classical economics introduced concepts like the 'invisible hand' and division of labor, establishing the framework for modern economic theory. -> correct