before the civil war began what republican ideas and proposals concerning indian territory alarmed the 5 tribes

Option B, The rise of the Knights of Labor led to support for a national populist political party in the late 1800s is the right answer.

The first important labor organization in America was set up with the foundation of the Knights of Labor in 1869. Knights of Labor drew the workers with their planned strikes and organized trade unions. Members of the organization promised to the people that they would improve the working conditions for them. They recommended a system of workers organizations to replace capitalism. Therefore, the emergence of the Knights of Labor began to promote a national populist party.