单选题 Ice Hockey or hockey, is a sport which is played on an ice rink. The game as we know it today started in Montreal, Canada, in 1875. Men's ice hockey became an official Winter Olympic game in 1924 but women first played ice hockey in the Olympics in 1998. There are six players in each team. Players skate on the ice and try to score a goal by shooting the puck into the other team's goal. To do this, they use a stick which is shaped like an 'L'. There are three twenty-minute periods. If both teams have the same score at the end, there is an overtime period or extra time. If the score is still the same after that period, there is a shootout. In a shootout, the players take turns trying to shoot the puck into the other team's goal. ( 3 )There are referees and officials on and near the ice to make sure no one breaks the rules. When players break the rules, they go to the 'penalty box' and sit there for two, four or five minutes until their penalty is over. One example of breaking the rules is moving the puck with your hands