Part A:
The correct answer is B. to limit corporations from controlling the American economy.
Farmers and industrial workers supported the Populist Party largely due to their grievances against the power and influence of large corporations in the economy, which they believed was detrimental to their interests.
Part B:
The correct answer is A. The expansion of railroad networks enabled ranchers to transport cattle to the East and expand into new markets.
The expansion of railroad networks played a crucial role in the cattle industry by allowing ranchers to efficiently transport their cattle to markets in the East, facilitating trade and economic growth for cattle kingdoms.