Disease had the most impact as the result of Columbian exchange because due to this exchange deadly diseases spread across all over the world with the travel and migration of people.
Columbian exchange was as exchange of plants, animals, humans, culture, disease, technology and other things to the Africa, America and many other countries. The Columbian exchange had negative as well as positive impact on both the continents.
Impact on Europe:
This exchange benefited the old world with the introduction of "new world crops" such as corn and potatoes. This exchange had negative impact as well. The transmission of epidemics and African people into slavery were some of negative impacts of Columbian exchange.
Impact on America:
The technology helped in advancement in agriculture and food cultivation while the exchange of disease increased the mortality rate among the Americans.
Answer:
He saw that Christianity could be harnessed to unite his Empire and achieve military success. From 313 AD onwards, Christian worship was tolerated within the Roman Empire. During the 4th Century, British Christianity became more visible but it had not yet won over the hearts and minds of the population.
Explanation:
Answer is in a photo. I couldn't attach it here, but I uploaded it to a file hosting. link below! Good Luck!

1. Germany (along with Italy and Japan)
2. United Nations (capitalist and socialist influence organization)
3. Warsaw Pact (communist organization)
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