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

There are some weightlifters on stage participating in weightlifting events. There are several spectators watching the event. one of the weightlifters

(a). successfully lifts the weight bar high up and then drops it down.;
(b). falls off of the bench.;
(c). jumps on a blading bar high up in the air.;
(d). falls off his seat onto his hands.;
The answer is:
(a).