This is a test of commonsense with single/multi-choices. Complete the next sentence:

After picking up speed on the powered boat, their friends jump off and have a great time. a line of rope

Select from: (1). is thrown behind them on the shore of the boat.. (2). is thrown out for them to grab onto and it begins.. (3). is strung between two trees and they are joined together by two people.. (4). is strung between two trees leading into a waterfall..
The answer is:
(2).