Explanation:

The given options are baseball, boxing, chess, wrestling, and squash. We need to identify the option that does not belong to the group.

1. Baseball:
Baseball is a popular sport that involves two teams of nine players each. It is played with a bat and ball and is known for its fielding and batting techniques. Baseball is a physical sport that requires coordination, teamwork, and strategy.

2. Boxing:
Boxing is a combat sport that involves two opponents fighting with their fists. It is a physical and contact sport where participants use defensive and offensive techniques to win the match. Boxing requires strength, agility, and endurance.

3. Chess:
Chess is a strategic board game that is played by two players on a checkered board. It is a mental sport that requires strategic thinking, planning, and problem-solving skills. Chess is known for its complexity and is often considered a game of intellect.

4. Wrestling:
Wrestling is a combat sport that involves grappling techniques and physical strength. It is a competitive sport where participants try to overpower each other using various holds and techniques. Wrestling requires physical fitness, agility, and technique.

5. Squash:
Squash is a racquet sport that is played by two players or teams on a four-walled court. It involves hitting a small rubber ball against the walls using a racquet. Squash requires speed, agility, and hand-eye coordination.

Conclusion:
From the given options, baseball does not belong to the group because it is the only option that is played with a bat and ball, while the other options involve either combat techniques (boxing and wrestling) or strategic thinking (chess) or racquet sport (squash). Therefore, the correct answer is option A) Baseball.