What was the effect of the old world during the columbian exchange

The Columbian exchange of crops affected both the Old World and the New. Amerindian crops that have crossed oceans—for example, maize to China and the white potato to Ireland—have been stimulants to population growth in the Old World.

d is the right answer

it was justfied as english were being brutal to the colonist and they needed to be stopped therfor causing a war but the moral over that is yes it was justifed