Which one of the following features is common is Earthworm, Butterfly Spider and Prawn

Options

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

Answer

To determine the common feature among Earthworm, Butterfly, Spider, and Prawn, we can analyze the characteristics of each organism step by step.

### Step-by-Step Solution:

1. **Identify the Organisms**:
- Earthworm: Belongs to the phylum Annelida.
- Butterfly: Belongs to the phylum Arthropoda (class Insecta).
- Spider: Belongs to the phylum Arthropoda (class Arachnida).
- Prawn: Belongs to the phylum Arthropoda (class Crustacea).

2. **Analyze the Features**:
We need to consider the features that might be common among these organisms. The options to consider are:
- A) Setae
- B) Antennae
- C) Ventral nerve cord
- D) Nephridia

3. **Evaluate Each Feature**:
- **Setae**: These are bristle-like structures found in earthworms for locomotion. They are not present in butterflies, spiders, or prawns. Therefore, this feature is not common.
- **Antennae**: Antennae are sensory organs found in arthropods (butterflies, spiders, and prawns), but they are not present in earthworms. Thus, this feature is not common either.
- **Ventral Nerve Cord**: All four organisms have a ventral nerve cord. This is a characteristic of non-chordates, including annelids and arthropods. Therefore, this feature is common among all four organisms.
- **Nephridia**: Nephridia are excretory structures found in earthworms, but they are not present in arthropods. Instead, arthropods have Malpighian tubules for excretion. Hence, this feature is not common.

4. **Conclusion**:
The common feature among Earthworm, Butterfly, Spider, and Prawn is the **ventral nerve cord**.

### Final Answer:
The common feature is the **ventral nerve cord**.