The missing word is Compensation.
Alfred Adler was known to be a medical doctor, a psychotherapist and is also a founder of the of the school of individual psychology.
According to Adler, individual psychology has got to do with this case wherein Ethan develops strength in other areas such as the compensation. In Adler's theory and principle, psychology owns compensation and overcompensation.
People who live in America can simply call themselves American now, as opposed to earlier when the area was divided into various countries.
<u>Explanation: </u>
This fact is the best out of the options that fits the description of the singular fact that best supports thee claim of modern life being less violent as compared to more and more of our evolutionary past.
This fact states that the people who were earlier divided into the countries and lived in a constant state of war, are now able to live together in a peaceful manner, thus stepping up from their evolutionary past and becoming less violent as they step into an era of modernization.
The American Revolution led to the Loyalists (Tories, to you Americans) flooding north and helping to populate the Maritime Provinces and what became the Eastern Townships of Quebec. They also, pretty much on their own, created what's now Ontario.
