Answer:
a. break the economic grip of the railroads through farmers' cooperatives.
Explanation:
Farmers' Alliance was an American agrarian economic movement created by the farmers living and farming in the United States of America during the 1870s and 1880s. The Farmers' Alliance was aimed and focused on improving the economic conditions for all American farmers to grow, develop and flourish excellently through the establishment of cooperatives and political advocacy groups.
Furthermore, the Farmers' Alliance believed majority of the economic problem and challenges was caused by industrial monopolies, eastern bank and railroads.
Hence, the Farmers' Alliance was originally formed in order to break the economic grip considered to be caused by the railroads, through the establishment of farmers' cooperatives.