In grasses, the vigorous and quick growth occurs due to

Options

A. sucker
B. runner
C. stolon
D. offset

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks why grasses exhibit vigorous and quick growth. This involves identifying the mechanisms or structures responsible for this growth.

2. **Identifying Growth Mechanisms**: In grasses, the primary mechanisms for rapid growth are modifications of the stem. The key types of stem modifications that contribute to this growth are:
- Runners
- Suckers
- Stolons
- Offsets

3. **Explaining Runners**: Runners are horizontal branches that grow along the surface of the soil. When these runners extend, they can produce new plants at various points along their length. This allows for quick propagation and contributes significantly to the overall growth of grass.

4. **Explaining Suckers**: Suckers are lateral branches that emerge from the axillary buds of the aerial parts of the grass plant. These suckers can grow into new plants, further enhancing the grass's ability to spread and grow quickly.

5. **Explaining Stolons**: Stolons are similar to runners but typically grow underground. They also spread horizontally and can give rise to new plants, contributing to the grass's vigorous growth.

6. **Explaining Offsets**: Offsets are a type of runner that is shorter and thicker, usually found at the apex of the plant, where a cluster of leaves is present. They also help in the propagation of new plants.

7. **Conclusion**: While all these structures contribute to the growth of grasses, the primary reason for their vigorous and quick growth is due to the presence of runners, which allow for rapid horizontal expansion and the formation of new plants.

**Final Answer**: In grasses, the vigorous and quick growth occurs due to runners.

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