Please choose the correct ending to complete the given sentence: BMX: The bikers are going over a curbed surface at full speed. There are several other bikers doing the same activity on another curved surface. there

Ending1: are five bikers wearing helmets standing ready to start a race. Ending2: are several other spectators kneeling on the curbs helping the group go over the top. Ending3: is a further change of event. Ending4: 's also a bull in a snowy area.

Answer format: ending1/ending2/ending3/ending4