Which one of the following organisms has a cellular respiratory pigment dissolved in plasma and is also a predaceous carnivore and shows matriphagy?

Options

A. Scorpion
B. Cockroach
C. Earthworm
D. Sea cucumber

Explanation

To solve the question, we need to identify which organism among the given options has the following characteristics:

1. A cellular respiratory pigment dissolved in plasma.
2. Is a predaceous carnivore.
3. Exhibits matriphagy.

Let's analyze each option step by step:

### Step 1: Analyze the Options
- **Scorpion**: Scorpions are known to have hemocyanin as their respiratory pigment, which is dissolved in their plasma. They are also predaceous carnivores, feeding on insects and other small animals. Additionally, some species of scorpions exhibit matriphagy, where the young consume the mother after birth.

- **Cockroach**: Cockroaches have a respiratory pigment called hemolymph, but they do not exhibit matriphagy. They are omnivorous rather than strictly carnivorous.

- **Earthworm**: Earthworms primarily feed on organic matter and are not predaceous carnivores. They do not exhibit matriphagy and have hemoglobin as their respiratory pigment, which is not dissolved in plasma.

- **Sea Cucumber**: Sea cucumbers are not predaceous carnivores; they are detritivores and feed on organic matter. They do not exhibit matriphagy and have a different type of respiratory pigment.

### Step 2: Conclusion
Based on the analysis:
- The only organism that meets all three criteria (cellular respiratory pigment dissolved in plasma, predaceous carnivore, and exhibits matriphagy) is the **Scorpion**.

### Final Answer
The correct answer is **Scorpion**.

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