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

After, the woman and her daughter are seen on a flat standing ski lift with large donut tubes following behind them. once they

a. are on the ground, the lady sets the baby in the tube tubes and begins walking on the snow. b. begin, an example of a snowboard is shown in the background with lights flashing in the middle. c. are at the top, they get into the tubes and race to the bottom along with several other people who are also at the place. d. are all all in the compartment, the teen pulls the stick and the mother gets on the side pushing her daughter.
The answer is:
c.