Explain this question more please
From what I can gather, the answer is either C. Many came to join family already in the United States, or D. Many were attracted by the opportunities to fight in the Civil War. (Sorry if it doesn't help).
The correct answer to this question is letter "d. a set number." Exit "immigration was restricted by assigning each nationality a quota based on its representation in past u.s. census figures." in this passage, the word <span>quota means a set of number.</span>
