Read this story beginning.
Sandra dumped a bucket of water onto the hot sand in front of her. A little of the water splashed up on her, but since she was in her bathing suit it didn't matter. She stirred the water and sand with her hands until she had a thick mixture. Then she began piling up the sand to build a castle.
Which sentence would provide the most conflict, if it were the next line in the story?

A) It certainly was a beautiful day.

B) Sandra had never been happier.

C) Suddenly, a wave washed over Sandra's castle.