How must a passenger sit on an ordinary two-wheeled motorcycle according to Chinese traffic safety regulations?

1. Sitting side-saddle with both legs on one side for easy dismounting
2. Sitting astride facing forward with feet on the passenger footrests (正向骑坐，不得侧向骑坐)
3. Standing on the rear footpegs while holding the driver's shoulders
4. Sitting between the driver and the fuel tank