A dorsal and hollow central nervous system is found in

Options

A. Bufo
B. Loligo
C. Dentalium
D. Limulus

Answer

To solve the question regarding which organism has a dorsal and hollow central nervous system, we will follow these steps:

### Step 1: Understand the Characteristics
The dorsal hollow central nervous system is a characteristic feature of vertebrates, specifically those belonging to the phylum Chordata. This system is formed from the ectoderm during embryonic development.

### Step 2: Analyze the Options
We need to evaluate the options provided to identify which one belongs to the group that possesses a dorsal hollow central nervous system. The options given are:
1. Bufo (Amphibia)
2. Loligo (Mollusk)
3. Dentalium (Mollusk)
4. Limulus (Arthropoda)

### Step 3: Identify the Vertebrate
- **Bufo (Amphibia)**: This is a genus of amphibians, which are vertebrates and thus possess a dorsal hollow central nervous system.
- **Loligo (Mollusk)**: This is a genus of cephalopod mollusks, which are invertebrates and do not have a dorsal hollow central nervous system.
- **Dentalium (Mollusk)**: This is another type of mollusk, also invertebrate, lacking the dorsal hollow nerve cord.
- **Limulus (Arthropoda)**: This is a horseshoe crab, which is an invertebrate and does not possess a dorsal hollow central nervous system.

### Step 4: Conclusion
From the analysis, the only organism that has a dorsal and hollow central nervous system is **Bufo (Amphibia)**.

### Final Answer
**Bufo (Amphibia)** is the correct answer as it is a vertebrate that possesses a dorsal hollow central nervous system.

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