Some stems are modified for the storage of food. They are :

Options

A. rhizomes of ginger
B. tubers of potatoes
C. corms of aroids
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding Modified Stems**: Some stems in plants are modified to serve specific functions, one of which is the storage of food. These modifications allow plants to store nutrients and energy in the form of starch, especially in adverse conditions.

2. **Identifying Examples**: The question asks for examples of stems modified for food storage. The examples provided in the video include:
- **Rhizomes**: These are underground stems that grow horizontally. An example is ginger, which stores starch.
- **Tubers**: These are swollen underground stems that also serve as storage organs. The potato is a well-known example of a tuber.
- **Corms**: These are swollen underground stems that serve as storage organs and help the plant survive harsh conditions. They are often found in plants like arrowhead.

3. **Conclusion**: Based on the examples discussed, we can conclude that:
- Rhizomes (like ginger)
- Tubers (like potato)
- Corms (like those from arrowhead)

All of these are modified stems that serve the purpose of food storage.

4. **Final Answer**: Therefore, the answer to the question is: **All of the following are modified stems for food storage: rhizomes of ginger, tubers of potato, and corms of arrowhead.**

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