B. Confederate states refused to send troops to the US army.
The answer is Caste system (A)
An interest group (also called an advocacy group, lobbying group,
pressure group, or special interest) is a group, however loosely or
tightly organized, that is determined to encourage or prevent changes in
public policy without trying to be elected.
So based off this knowledge, we can eliminate C. :)
I don't think it's A or B because they are more concerned with change
and advocacy than a "free time" thing.
So going with this definition, I'd go with D ;)
B. is the right answer because the north america have in common they all lived in the small family units.
good luck
Answer:
B, Nixon
Explanation:
Nixon was the American President during the last half of the Vietnam War
