I think you forgot to give the options along with this question. I am answering the question based on my research and knowledge. The outrage against Lindbergh's speech led to a steep decline in the membership of Ku Klux Klan. I hope that the answer has come to your help.
Answer:
Both led troops US troops in the Mexican-American War.
Writing a constitution mirrored white society, and was an attempt to help Cherokees be accepted by whites.
The correct answer is increase in industrialization.
Due to the technological advancements of the mid-late 1800's, Americans started to rely more on industry rather than farming. Working in a factory rather than a farm had its perks. People who worked in a factory had guaranteed wages, whereas in farming the amount of money a person makes is dependent on several different factors like the amount of people who want to buy your products, climate, location, etc.