Explanation:

- The question states that it was raining, which implies that the outdoor activities might not be possible or enjoyable for the boys.
- The correct answer is option 'B' - inside, as it suggests that the boys played indoors due to the rain.

Reasoning:

- When it rains, it becomes difficult or uncomfortable to play outside due to wet conditions.
- Playing inside provides a dry and safe environment for the boys to engage in various activities.

Importance of playing indoors:

- Playing indoors allows children to stay active and have fun even when the weather is not suitable for outdoor activities.
- It promotes creativity, problem-solving, and imaginative play.
- Indoor games can include board games, puzzles, building blocks, pretend play, and more.
- It also helps in developing social skills as children can play together and learn to cooperate and share.

Benefits of playing indoors:

- Playing inside helps in improving hand-eye coordination, motor skills, and cognitive abilities.
- It stimulates brain development and enhances concentration and focus.
- Indoor play can be a great way for children to learn and explore new things.
- It also provides a safe environment where parents can easily supervise their children.

Conclusion:

- In this question, the boys played indoors as it was raining. Playing inside not only provides entertainment but also offers numerous developmental benefits for children.