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【单选题】
Today, bicycles are elegantly simple machines that are common around the world. Many people ride bicycles for recreation, whereas others use them as a means of transportation. The first bicycle, called a draisienne, was invented in Germany in 1818 by Baron Karl de Drais de Sauerbrun. Because it was made of wood, the draisienne wasn’t very durable nor did it have pedals. Riders moved it by pushing their feet against the ground. In 1839, Kirkpatrick Macmillan, a Scottish blacksmith, invented a much better bicycle. Macmillan’s machine had tires with iron rims to keep them from getting worn down. He also used foot-operated cranks, similar to pedals, so his bicycle could be ridden at a quick pace. It didn’t look much like the modern bicycle, though, because its back wheel was substantially larger than its front wheel. Although Macmillan’s bicy- cles could be ridden easily, they were never pro- duced in large numbers. In 1861, Frenchman Pierre Michaux and his brother Ernest invented a bicycle with an improved crank mechanism. They called their bicycle a vélocipède, but most people called it a “bone shaker” because of the jarring effect of the wood and iron frame. Despite the unflatter- ing nickname, the vélocipède was a hit. After a few years, the Michaux family was making hundreds of the machines annually, mostly for fun-seeking young people. Ten years later, James Starley, an English inventor, made several innovations that revolu- tionized bicycle design. He made the front wheel many times larger than the back wheel, put a gear on the pedals to make the bicycle more efficient, and lightened the wheels by using wire spokes. Although this bicycle was much lighter and less tiring to ride, it was still clumsy, extremely top- heavy, and ridden mostly for entertainment. It wasn’t until 1874 that the first truly mod- ern bicycle appeared on the scene. Invented by another Englishman, H.J. Lawson, the safety bicy- cle would look familiar to today’s cyclists. The safety bicycle had equal-sized wheels, which made it much less prone to toppling over. Lawson also attached a chain to the pedals to drive the rear wheel. By 1893, the safety bicycle had been further improved with air-filled rubber tires, a diamond- shaped frame, and easy braking. With the improvements provided by Lawson, bicycles became extremely popular and useful for trans- portation. Today, they are built, used, and enjoyed all over the world. The first person to use a gear system on bicy- cles was
A.
H.J. Lawson.
B.
Kirkpatrick Macmillan.
C.
Pierre Michaux.
D.
James Starley.
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