C. By prohibiting the manufacturing and sale of alcohol
Answer: Unions in the 1920s were harmed by rising wages which made it harder to attract new members.
Explanation: Give me the brainiest
Because the US had a great geographical location which shileded them from immediate contact with any military force. This was one thing, another thing was that they were lending money to the different European nations which they had to return after some time. All of this enabled the US to catapult itself and become a world power.
Benjamin Franklin helped to negotiate this treaty.