What made the Knights of Labor interesting and important?

Question

Select one:
a. They were the first group to try and organize unskilled, as well as skilled, workers
b. They were the first group to try and organize women, as well as men.
c. They were the first group to organize blacks, alongside whites.
d. They were the first group to do all of the above.

I think d

Answer 1

D is correct.

Answer 2

http://www.u-s-history.com/pages/h933.html