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 against the ground. This was called a 'hobby horse.' Later, in the 1860s, pedals were added to the front wheel, creating the 'penny-farthing.' However, these were dangerous due to their large front wheel. It wasn't until the 1880s that the 'safety bicycle' appeared, with two equal-sized wheels and a chain drive, making it much safer and more practical for everyday use.
❓ 根据讲座内容，安全自行车相较于早期型号的主要优势是什么？
A. 它有一个更大的前轮以提高速度。
B. 由于采用了链传动设计，它更加安全。
C. 它更轻便，更容易携带。
D. 它比前轮大后轮小的自行车维护起来更省事。
✅ 正确答案
It was safer because of its design and chain drive.