Explanation:

- Correct Answer: 3 Zhangjiakou

- In January 2020, China introduced the world's first high-speed driverless bullet train that operates between Beijing and Zhangjiakou. This was notably used for the 2022 Winter Olympics, providing rapid transit between the two cities.

- Option 1: Lhasa

- Lhasa is the capital of the Tibet Autonomous Region and is connected by the Qinghai-Tibet Railway, which is not a high-speed line and does not incorporate driverless technology.

- Option 2: Shanghai

- Beijing and Shanghai are connected by a high-speed rail line, but this operation is not driverless. The Beijing-Shanghai route is one of the busiest in China.

- Option 4: Haikou

- Haikou is the capital of Hainan Province in southern China. The high-speed railways in this region focus on serving the island; there are no direct driverless high-speed train connections to Beijing.