The correct answer is option 'A' - Gardener.

Explanation:
A school garden is a designated area within a school where students learn about gardening, agriculture, and environmental sustainability. It provides hands-on experiences for students to connect with nature, learn about plants and their growth cycles, and develop important life skills such as responsibility, teamwork, and problem-solving.

The role of a gardener in a school garden is crucial as they are responsible for maintaining the garden and ensuring its proper care. Here is a detailed explanation of why the gardener is the correct answer:

1. Responsibilities of a Gardener:
- Planting and maintaining various plants, flowers, and vegetables in the garden.
- Watering the plants regularly and providing them with proper nutrients.
- Weeding and removing unwanted plants to ensure the growth of desired plants.
- Pruning and trimming plants to maintain their health and shape.
- Controlling pests and diseases that may affect the plants.
- Ensuring the garden is clean and tidy.

2. Expertise and Knowledge:
- A gardener has specific knowledge and expertise in horticulture and gardening techniques.
- They understand the needs of different plants and can provide appropriate care.
- They can identify pests, diseases, and other issues that may affect the plants and take necessary actions to address them.

3. Time Commitment:
- Maintaining a school garden requires regular time and effort.
- A gardener can dedicate sufficient time to the garden, ensuring its proper care and maintenance.
- Teachers and other staff members may have other responsibilities and may not have enough time to devote to the garden.

4. Ensuring Safety:
- A gardener can ensure the safety of the students while working in the garden.
- They can guide students in using gardening tools safely and teach them about potential hazards in the garden.

In conclusion, a gardener is the most suitable person to take care of the school garden. They have the necessary expertise, knowledge, and time commitment to ensure the garden thrives and provides valuable learning experiences for the students.