Which one contains only mesodermal structure?

Options

A. Liver,heart,blood, and muscles
B. Notochord, heart, blood and bone
C. Liver,heart,blood and bone
D. Liver,blood ,notochord and muscles.

Answer

To determine which option contains only mesodermal structures, we need to analyze the structures listed in each option and identify their embryonic origins.

### Step-by-Step Solution:

1. **Understanding Germ Layers**:
- The three primary germ layers formed during embryonic development are ectoderm, mesoderm, and endoderm. Each layer gives rise to specific tissues and organs in the body.
- **Ectoderm**: Develops into the nervous system, skin, and related structures.
- **Mesoderm**: Forms muscles, bones, blood, heart, and connective tissues.
- **Endoderm**: Gives rise to the gastrointestinal tract, liver, lungs, and other internal organs.

2. **Analyzing Each Option**:
- **Option A**: Liver (endoderm), heart (mesoderm), blood (mesoderm), muscles (mesoderm).
- Contains endodermal structure (liver), so this option is incorrect.
- **Option B**: Nauticalte (mesoderm), heart (mesoderm), blood (mesoderm), bone (mesoderm).
- All structures here are mesodermal, making this option a candidate for the correct answer.
- **Option C**: Liver (endoderm), heart (mesoderm), blood (mesoderm), bone (mesoderm).
- Contains endodermal structure (liver), so this option is incorrect.
- **Option D**: Liver (endoderm), blood (mesoderm), nauticalte (mesoderm), muscles (mesoderm).
- Contains endodermal structure (liver), so this option is incorrect.

3. **Conclusion**:
- After analyzing all options, only **Option B** (nauticalte, heart, blood, and bone) contains structures that are exclusively derived from the mesoderm.

### Final Answer:
The correct answer is **Option B: Nauticalte, heart, blood, and bone**.