Final answer:
The defense used when each player guards another player is called man-to-man defense. It is commonly used in team sports to prevent scoring opportunities.
Step-by-step explanation:
The defense that is used when each player guards another player is called the man-to-man defense. In this type of defense, each player is assigned to guard a specific opponent on the opposing team. The defender must closely watch their assigned player and try to prevent them from scoring or making plays.
For example, in basketball, if a team is using man-to-man defense, each defensive player will have a specific offensive player that they are responsible for guarding. They will stay close to their assigned player, trying to prevent them from getting open for a pass or making a shot.
Man-to-man defense is common in many team sports, including basketball, soccer, and lacrosse. It allows for close, individual coverage of opponents and can be effective in preventing scoring opportunities.