Read the following passage carefully and complete the sentences that follow by circling letter A, B, C or D as the correct answers I then mark your choice on the answer sheet.

     Most fairy tales in the world begin with "Once upon a time" and end with "They lived happily ever after," so we will begin in the same way. Once upon a time, there was a girl called Cinderella who did all the work in the kitchen while her lazy sister did nothing. One night, her sister went to a ball at the palace. Cinderella was left home, very sad. After a time, her fairy godmother appeared and told Cinderella that she could go to the ball — but to return home by midnight.

     So she went to the ball in a beautiful dress in a wonderful coach. She danced with the prince but at midnight she ran back home, leaving one of her shoes on her dancing floor. The prince wanted to see her again and went to every house in the capital until he found that the shoe was the right size for Cinderella. She and the prince were married and lived happily ever after.

The word "ball" in the first sentence of paragraph 3 means _______ .