I believe that would be B. Metal weapons and armor
Hope it helps!
There were many factors that led to the rise of political machines in American cities in the 18th, 19th, and 20th centuries. One of the major factors that led to the rise of political machines was the rise of immigrant populations who sought to gain and increase their influence in the political realm and served as a powerful political tool for political machines. Political machines worked to enfranchise these voters through a system of patronage, and bribes and would bring them out on election days to support politicians who paid political bosses or awarded government privileges to. Positive aspects of this system were that it gave some increased level of representation of immigrant populations and worked to enfranchise these new political groups. However, these machines led to a high level of corruption and hurt the meritocracy of government institutions at the time.
Millions of people moved during the Industrial Revolution. Some simply moved from a village to a town in the hope of finding work whilst others moved from one country to another in search of a better way of life. Some had no choice, transportation was a punishment for some crimes.
I think the answer to your question is Red Scare because I have never herd of the Red Smear before.
It called for protection of equal privileges for all countries trading with China and for the support of Chinese territorial and administrative integrity