Answer:
D. the original dynamo (power plant)
Explanation:
Edison once more combined inventions of other inventors (the steam engine, improved by James Watt and the rotary generator by Michael Faraday) to create the first dynamo, that was installed in a New York City power station in 1882.
That invention spread like fire across the US, with over a thousand installations within 8 years, to revolutionize the methods of delivering power.
