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During the Revolutionary War, a Yankee invented a submarine called the Turtle. A number of years later, Robert Fulton became interested in undersea craft. In 1800, he built the Nautilus. Then, during the American Civil War, another underwater craft was built.
WHAT IS THIS PASSAGE MAINLY ABOUT?
A) For many years man tried to find ways to travel underwater;
B) For many years Robert Fulton was interested in undersea craft;
C) Underwater crafts were very important during American Civil War;
D) For many years man tried many ways to win the Revolutionary War.
A) For many years man tried to find ways to travel underwater