How did european exploration affect the native american peoples?

Explanation:

Europeans carried a hidden enemy to the Indians: new diseases. Native peoples of America had no immunity to the diseases that European explorers and colonists brought with them. Diseases such as smallpox, influenza, measles, and even chicken pox proved deadly to American Indians.

in 1897, pershing became a tactical officer at west point, and that's where he was given the nickname "black jack." pershing's first name is "john," for which "jack" is a nickname, and he was a white man who commanded black troops. hence "black jack".

d is the best answer for this question.