The underground part of the plant is known as ___________

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the underground part of a plant. This part is located below the ground level.

2. **Identifying Plant Parts**: A plant consists of various parts, including the stem, leaves, flowers, and roots. The roots are the part that grows underground.

3. **Focusing on the Underground Part**: Since the question specifies the underground part, we need to focus on the roots. The roots anchor the plant in the soil and are essential for its growth.

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