Feature common to Leech, Cockroach and Scorpion is

Options

A. Ventral nerve cord
B. Nephridia
C. Antennae
D. Cephalisation.

Answer

To determine the feature common to leech, cockroach, and scorpion, we need to analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Phyla**:
- Leech belongs to the phylum **Annelida**.
- Cockroach and scorpion belong to the phylum **Arthropoda**.

2. **Examine Each Option**:
- **Option 1: Ventral Nerve Cord**:
- Both annelids (like leeches) and arthropods (like cockroaches and scorpions) possess a **ventral nerve cord**. This is a common feature among these organisms.
- **Option 2: Nephridia**:
- Nephridia are excretory structures found in annelids. While leeches have nephridia, cockroaches and scorpions do not possess this structure. Therefore, this option is not common to all three.
- **Option 3: Antenna**:
- Antennae are sensory appendages found in insects (like cockroaches) but are absent in leeches and scorpions. Thus, this option is also not common to all three.
- **Option 4: Cephalization**:
- Cephalization refers to the development of a distinct head region. While cockroaches and scorpions exhibit cephalization, leeches do not have a well-defined head. Hence, this option is not common to all three.

3. **Conclusion**:
- The only feature that is common to leech, cockroach, and scorpion is the **ventral nerve cord**. Therefore, the correct answer is **Option 1**.

### Final Answer:
The feature common to leech, cockroach, and scorpion is the **ventral nerve cord**.

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