A、Electricity. B、Steam. C、Water. D、Boats. B

In the early 1800s a new kind of power changed transportation and trade along the Mississippi River. This power was steam. People already knew how to use steam engines to run machines. Some people wanted to move boats in the same way. The first steamboat to travel on the Mississippi River was the "New Orleans." It made its first trip in 1811. It was a great success, and by 1819 there were 191 steamboats traveling on the long river.
    In the past, farmers whose products went to other parts of the country used steamboats. The manufacturers’ trade depended on cheap and easy transportation and they used the steamboats as well.
    Today many tourists come to travel on steamboats.