Multi-select problem: How does the next paragraph end?

They pick up speed and a young woman is skiing on the water at a very brisk pace. She goes back and forth and side to side in slow motion. the friends

Available choices:
 (a). continue skiing through the room going over several snowy slopes.
 (b). then hold the still image as they zoom in on her face as she goes quickly down the slopes.
 (c). look back to see how she is doing.
 (d). are holding a close close inspection of the bottom of the board as she goes down the slide.
(c).