Good morning, everyone. Today we're going to discuss the history of the bicycle. Now, many people assume that the bicycle was invented in the 19th century, and that's partly true. The first two-wheeled vehicle, called a 'velocipede', appeared around 1817, but it had no pedals. You had to push it with your feet. Later, in the 1860s, pedals were added to the front wheel, which made riding faster but also more dangerous. It wasn't until the late 1880s that the 'safety bicycle' with a chain drive and two equal-sized wheels was developed, and that design became the basis for modern bicycles.
❓ Nhược điểm chính của xe đạp có bàn đạp vào những năm 1860 là gì?
A. Nó quá chậm để sử dụng thực tế.
B. Việc giữ thăng bằng rất khó khăn và nguy hiểm.
C. Nó đòi hỏi quá nhiều sức lực thể chất.
D. Nó không được phép lưu thông trên đường công cộng.