Vegetative reproduction in onion occurs by:

Options

A. Offset
B. Bulb
C. Sucker
D. Rhizome

Answer

**Step-by-Step Solution:**

1. **Understanding Vegetative Reproduction**: Vegetative reproduction is a form of asexual reproduction where new plants grow from parts of the parent plant. This can occur through various structures such as bulbs, offsets, suckers, and rhizomes.

2. **Analyzing the Options**:
- **Option 1: Offset**: Offsets are small daughter plants that develop from the mother plant. They are typically found in aquatic plants like water hyacinth. Therefore, this option is incorrect for onion.

- **Option 2: Bulb**: Onions reproduce vegetatively through bulbs. A bulb is a storage organ that contains the plant's nutrients and can give rise to a new plant. This is the correct answer.

- **Option 3: Sucker**: Suckers are shoots that develop from the base of a plant or from its rhizome. They are commonly seen in plants like mint but are not the method of vegetative reproduction in onions. Hence, this option is incorrect.

- **Option 4: Rhizome**: Rhizomes are underground stems that can produce new shoots and roots. They are found in plants like ginger. Since onions do not reproduce through rhizomes, this option is also incorrect.

3. **Conclusion**: Based on the analysis, the correct answer to the question "Vegetative reproduction in onion occurs by:" is **bulb**.

**Final Answer**: Bulb

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