A conquistador is a Spanish explorer, like the ones that explored America. They were important since the Spanish would not have spread their empire without someone to lead the way.
An immunity is something that means you cannot get harmed by since you have already had it or have medication to make yourself invincible to that disease. It's like after having chicken pox, you can't get again.
I hope that this is the answer that you were looking for and it has helped you.
The answer is b,c,d. I hope this helps someone.
The person in question is Woodrow Wilson:
He was the president of the United States from 1913 to 1921, which means that he was the president before, during and after the First World War.
He was very active in the peace process after the war, including proposing the formation of the League of Nations.
They were for c.kept a lot of african americans from voting
I might be wrong but I believe it was Afghanistan...?