The world’s longest bullet train network has been established in which country?
[A]China
[B]Japan
[C]United States
[D]Germany

China
The world’s longest bullet train (or High-Speed Rail (HSR)) network with over 20,000 km of track has established in China. The network is part of the network of passenger-dedicated lines (PDLs) in service. The HSR in China refers to any railway in China with commercial train service at the speed of 200 km/h or higher.