Please choose the correct ending to complete the given sentence: River tubing: People are seen riding on a tube down a river. the people

Ending1: ride down while being pulled by a person on a cable. Ending2: turn on their tubes, then go down the hills. Ending3: hold their hands up and smile while still riding down. Ending4: keep riding down the river as bubbles come up from below.

Answer format: ending1/ending2/ending3/ending4