Final answer:
Farmers did not share in the prosperity of the 1920s due to falling crop prices and lack of federal price support, leading to financial struggles.
Step-by-step explanation:
The group that did not share in the prosperity of the 1920s is C. Farmers because crop prices fell during this period. After the end of World War I, there was a mistaken belief that overproduction would help farmers' profits. Instead, this strategy led to a decrease in crop prices. Furthermore, President Coolidge vetoed attempts for federal price support leaving farmers in a dire situation. Many farmers defaulted on their loans and this had a domino effect on rural banks.