Which of the following is correctly matched ?

Options

A. Haemoglobin in RBC - earthworm
B. Haemoglobin in WBC - earthworm
C. Haemocyanin in plasma - prawn
D. Haemocyain in plasma - starfish

Answer

To determine which of the following options is correctly matched, we will analyze each option based on the oxygen-carrying pigments and the organisms mentioned.

### Step-by-Step Solution:

1. **Analyze the first option: Hemoglobin in RBC in earthworm.**
- Earthworms belong to the phylum Annelida.
- They do have hemoglobin, but it is not found in red blood cells (RBCs) as in vertebrates. Instead, hemoglobin is present freely in the plasma.
- **Conclusion:** This is an incorrect match.

2. **Analyze the second option: Hemoglobin in WBC in earthworm.**
- Similar to the first option, hemoglobin in earthworms is not found in white blood cells (WBCs) either.
- Hemoglobin is present in the plasma, not in any blood cells.
- **Conclusion:** This is also an incorrect match.

3. **Analyze the third option: Hemocyanin in plasma in case of prawn.**
- Prawns belong to the phylum Arthropoda.
- They possess hemocyanin, which is a copper-containing pigment found in their plasma.
- Hemocyanin is responsible for transporting oxygen and gives the plasma a blue color.
- **Conclusion:** This is a correct match.

4. **Analyze the fourth option: Hemocyanin in plasma of starfish.**
- Starfish belong to the phylum Echinodermata.
- They do not have hemocyanin or any other pigment for oxygen transport. Instead, they rely on a water vascular system for gas exchange.
- **Conclusion:** This is an incorrect match.

### Final Answer:
The correct match is **option number three: Hemocyanin in plasma in case of prawns.**

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