In today's lecture, we'll discuss the history of the bicycle. The first bicycle, invented in the early 19th century, had no pedals; riders pushed their feet along the ground. Later, the penny-farthing, with its large front wheel, became popular in the 1870s, but it was dangerous due to its height. The safety bicycle, introduced in 1885, featured equal-sized wheels and a chain drive, making it much more stable. This design quickly replaced the penny-farthing and is the basis for modern bicycles. Interestingly, the pneumatic tire, invented in 1888, was originally developed for bicycles, not cars, which greatly improved comfort and speed.
❓ 安全自行车相较于前轮大后轮小的自行车（Penny-farthing）的主要优势是什么？
A. A. 它更轻便，更容易携带。
B. B. 它采用了链传动和等大的车轮，使其更加稳定。
C. C. 这是第一辆装有脚踏板的自行车。
D. D. 它的制造成本比早期型号更低。
✅ 正确答案
B. It had a chain drive and equal-sized wheels, making it more stable.