How are we going to do this for you and you do not have a book
Answer:
Europeans introduced new diseases, killing indigenous natives.
Explanation:
On arriving this places, the Europeans brought with them diseases that were originally not known to these indigenous people. The indigenous people had a large mortality rate due to these diseases because their immune systems were unfamiliar with these diseases.
I believe the answer is: Rationalization
In psychology, rationalization refers to the act of justifying negative behaviors/outcome in your life even if the justification is inappropriate.
This action often being done by someone who are not willing to face the truth and refused to held accountable for the outcome that happened in their life.