Which invention had the greatest impact on American life and business in the twenties?

The correct answer to this question isAutomobile. The first was invented in 1885 by Karl Benz. At that time, the car could only go as fast as 16 km per hour. Automobiles are essential because they help people get to their destinations more quickly. Before cars, people would walk, take train rides, or use horse and buggies, which aren't as efficient as cars.

It also gives person independence and the freedom to go to and from however they wish. It can also help a person get a better job that may require a car and in turn, allow them to have more opportunities.