A horizontal underground stem is a
Or
Ginger plant has an underground stem which is

Options

A. corm
B. phylloclade
C. rhizome
D. rhizoid

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the identification of a horizontal underground stem and specifically mentions the ginger plant, which has a particular type of underground stem.

2. **Identifying the Options:**
The options provided are:
- Comb
- Phylloclad
- Rhizome
- Rhizoid

3. **Analyzing Each Option:**
- **Comb:** This is a rounded underground storage organ. It does not fit the description of a horizontal underground stem.
- **Phylloclad:** This refers to a flattened branch or stem that resembles and functions like a leaf. It is not an underground stem, so this option is incorrect.
- **Rhizome:** A rhizome is a modified stem that grows horizontally underground. It produces roots and shoots from its nodes and is known as a creeping rootstock. This fits the description of the ginger plant's underground stem.
- **Rhizoid:** This is a filamentous outgrowth or root-like structure found on the underside of the thallus in some lower plants. It does not represent a horizontal underground stem.

4. **Conclusion:**
Based on the analysis, the correct answer to the question is **Rhizome**. The ginger plant has an underground stem which is a rhizome.

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