Which one is odd

Options

A. Allium cepa
B. Helianthus annuus
C. Brassica juncea
D. Arachis hypogea

Answer

To determine which one is the odd one out among the given options, we will analyze each option based on their botanical classification, specifically focusing on their families and whether they are monocots or dicots.

### Step-by-Step Solution:

1. **Identify the first option: Allium sepa**
- Common Name: Onion
- Botanical Family: Liliaceae
- Classification: Monocotyledon (Monocot)

2. **Identify the second option: Helianthus annuus**
- Common Name: Sunflower
- Botanical Family: Asteraceae
- Classification: Dicotyledon (Dicot)

3. **Identify the third option: Brassica juncea**
- Common Name: Mustard
- Botanical Family: Brassicaceae
- Classification: Dicotyledon (Dicot)

4. **Identify the fourth option: Arachis hypogea**
- Common Name: Groundnut (Peanut)
- Botanical Family: Fabaceae
- Classification: Dicotyledon (Dicot)

5. **Comparison of Classifications:**
- Allium sepa (Onion) is a monocot.
- Helianthus annuus (Sunflower), Brassica juncea (Mustard), and Arachis hypogea (Groundnut) are all dicots.

6. **Conclusion:**
- Since Allium sepa is the only monocot among the options, while the others are dicots, it is the odd one out.

### Final Answer:
The odd one out is **Allium sepa** (Onion).

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