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

A group is dancing inside a gym. they

Available options:
[I] are moving in unison, keeping time to the beat.
[II] engage in martial arts moves.
[III] are holding onto a pole to balance as they dance.
[IV] have a routine going on that involves men handling weight in different places and on biking benches.
The answer is:
[I]