What was the main reason for the remarkable growth in population during the first half of the eighteenth century?

The main reason was the rise of the Industrial Revolution in England and later in the rest of Europe.

Explanation:

The eighteenth century was the period in history were the Industrial Revolution began. Firstly in England, prodcution and consumption of goods  rapidly rose with the invention of machines for mass production and other technogies that boosted the industry to levels never seen before.  Even though there were some issues that came as result of the indstrulization, It is also true that wealth increased for most of the people who worked in the factories and cities adapted to the new amount of incoming people from the countrysides providing more a better services for the welfare of the citizens. As a result, population grew remarkably in England and later in the rest of Europe

i think the answer is a and i hope this ; ))

the main concern with the first draft of the articles of confederation was too much power in the state governments.