Identify the right combination
(a) carrot-tuberous root- head inflorescence
(b) onion-bulb-corymb
(c) colocasia-Rhizome-spadix
(d) bougainvillea-thorns-cymula

Options

A. carrot-tuberous root- head inflorescence
B. onion-bulb-corymb
C. colocasia-Rhizome-spadix
D. bougainvillea-thorns-cymula.

Answer

To solve the question, we need to analyze each option and identify whether the combinations of plants, their modifications, and types of inflorescence are correct.

### Step-by-Step Solution:

1. **Option (a): Carrot - Tuberous Root - Head Inflorescence**
- Carrot is a modified root known as a tuberous root.
- However, the inflorescence type associated with carrot is not a head inflorescence; it is an umbel inflorescence.
- **Conclusion**: This combination is incorrect.

2. **Option (b): Onion - Bulb - Corymb**
- Onion is a modified stem that forms a bulb.
- The inflorescence type for onion is not corymb; it is actually umbellate.
- **Conclusion**: This combination is incorrect.

3. **Option (c): Colocasia - Rhizome - Spadix**
- Colocasia is a type of stem modification, but it is known for forming a corm, not a rhizome.
- The inflorescence type is indeed a spadix.
- **Conclusion**: This combination is incorrect due to the wrong type of modification.

4. **Option (d): Bougainvillea - Thorns - Cymula**
- Bougainvillea has modified stems that form thorns for protection.
- The type of inflorescence it possesses is indeed cymose, which can be referred to as cymula.
- **Conclusion**: This combination is correct.

### Final Answer:
The correct combination is **(d) Bougainvillea - Thorns - Cymula**.

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