Karl Marx most assuredly did not believe in the Invisible Hand, nor did he invent the concept, so he would not be a good choice. Voltaire was not particularly interested in the study of economics, so he would not be a good answer here. John Locke was a philosopher but he did not invent the concept of the Invisible Hand, so he would not be the correct answer. Jonathan Swift was a satirist, but he did not study economics as a discipline, so he would not be the best answer. Lastly, Adam Smith did both of the things in question, so he would be the best answer.

The United Kingdom has continued to use the British Pound as its currency, despite being a member of the European Union. The other nations do use the Euro, and are therefore incorrect.

Inflation generally occurs when there is too much money flooded into a society without a proportional increase in the level of production. In sixteenth-century Europe, almost all currency was backed by gold, silver, or some other precious metal, so when gold and silver flooded into Europe from the New World, it led to rampant inflation until the money could be reinvested into increasing the level of production.

Thomas Malthus wrote his famous work An Essay on the Principle of Population in 1798, and it quickly came to have a profound effect on the government policies of Western European countries and the development of several ideas, such as the theory of natural selection. It states that population will naturally increase at a greater rate than the ability of that population to sustain itself—essentially, that unchecked population growth will lead to poverty and a lower standard of living. Malthus based his theory, in part, on his belief that human reproduction operates on an exponential model whereas production operates on an arithmetic model. The British government in particular during the Industrial Revolution took Malthusian theories to heart and attempted to limit the growth of the working class.

Adam Smith is one of the most influential economists in European history. His magnum opus The Wealth of Nations was published in 1776 and is one of the earliest-known works advocating for free-market laissez-faire capitalism. It also touches on issues like division of labor, class structure, and government intervention in the economy.

Banking, as we generally understand it, can be loosely traced to the Italian city-states at the height of the Italian Renaissance; however, it did not really emerge as an institution that could extend credit and support corporations until the banking revolution that began in the Dutch Republic in the seventeenth and eighteenth centuries and quickly spread to Britain and then around Western Europe.

Britain, like most other countries at the time, embraced mercantalism in the initial period of European colonialism and expansion; however, the British switched their economic policy to the promotion of free market capitalism once their naval power and commercial might made doing so advantageous. This has been widely criticized by politicians and thinkers in other countries who decry Britain’s emphasis on “fairness” and “economic equality” when, from their perspective, the British only embraced it themselves after they had become wealthy from the exploitation of other countries' raw resources and peoples.

The mercantilist system drove the first wave of European exploration and colonization from the fifteenth to the eighteenth centuries. It depended upon overseas colonies for raw resources which were then shipped to the metropole (home country) to be turned into manufactured goods. These manufactured goods, the theory goes, would then be sold around Europe, allowing the metropole to develop a favorable balance of trade. Over time, many of the colonies began to provide a market for the sale of manufactured goods or provided workers to fuel the system, but the primary purpose for establishing overseas colonies in the mercantilist system was almost always to provide the home country with much-needed raw resources.

In 1394, Giovanni de Medici founded the Medici Bank in Florence, which over the next century became the most powerful and influential bank in all of Europe. Through this influence, the Medici family slowly gained political power over the city of Florence, which was asserting itself as the most powerful Italian city-state. The Medici family would become hereditary Dukes of Florence, produce four popes, and have two women become queen regents of France.

The Iron Law of Wages is an important principle of capitalist economics usually credited to David Ricardo, although sometimes it is credited to Thomas Malthus. It states that in the long term, the amount of money that a worker receives for labor will always tend towards the bare minimum needed to keep the worker alive and working.