Why didn't early bicycles look much like today's models?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions front 43 to 50.

You might be surprised to know that bicycles have existed for less than two hundred years. Though the earliest comes from a sketch said to be from 1534 and attributed to Gian Giacomo, there are several early but unverified claims for the invention of the modem bicycle. No one is sure who invented this popular two- wheeled machine, but it was probably either the German Karl von Drais, in 1817, or the American W K Clarkson, in 1819. The early models didn't look much like the bicycles of today. The front wheel was much bigger than the back one, and also there weren't any pedals - riders had to move themselves forward by pushing their feet against the ground. Pedals finally arrived in the 1840s, and in 1879 an Englishman named Henry Lawson had the idea of connecting them to the back wheel with a chain. Gears, which made things much easier for those cycling uphill, first appeared in the 1890s.

There are now approximately one billion bicycles in the world - more than twice the total number of cars - and they are the main form of transport in some developing countries. They have to compete with cars on the streets of all the world's cities, and the two forms of transport don't always mix well. In London in 2005, for example, over 300 cyclists were either killed or seriously injured in accidents involving cars. Even though bicycles are much more environmentally friendly than cars, most governments don't do much to encourage people to ride rather than drive. In China, which is famous for having a huge number of bicycles (about 200 million), the authorities in the city of Shanghai even banned cycling for a while in 2003.

Cycling is on the rise is the United Kingdom, and the number of annual journeys made by bike in London has increased 50% over the last five years. Experts say there is a mixture of reasons for this boom: concerns about the environment, the desire to keep fit, and also the fact that cycling is often not only cheaper but also quicker than travelling by car.

However, although one in three British adults owns a bicycle, they still don't use them nearly as much as they could. Bikes are used for a mere 2% of journeys in the UK, while the figure for the Netherlands is an impressive 27%.

Cycling is becoming more popular as a competitive sport, and the most famous race is of course the three-week Tour de France, which takes place every July. American Lance Armstrong won it every year from 1999 to 2005 - one of the greatest individual sporting achievements of all time.