You have discovered an animal having characters like, triploblastic, bilateral symmetry, coelomate, chitinous exoskeleton, head, thorax and abdomen as bidy parts, and jointed appendages.
You should place the animal under

Options

A. mollusca
B. arthropoda
C. annelida
D. echinodermata

Answer

To classify the discovered animal based on the provided characteristics, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Characteristics**:
- The animal is described as triploblastic, which means it has three germ layers (ectoderm, mesoderm, and endoderm).
- It exhibits bilateral symmetry, indicating that it can be divided into two mirror-image halves.
- It is coelomate, meaning it has a true coelom (body cavity).
- It has a chitinous exoskeleton, which is a hard outer structure made of chitin.
- The body is divided into three parts: head, thorax, and abdomen.
- It possesses jointed appendages.

2. **Analyze the Options**:
- **Mollusca**: Typically characterized by a soft body, often with a shell, which does not match the characteristics given (no mention of a shell).
- **Arthropoda**: Known for having a chitinous exoskeleton, jointed appendages, bilateral symmetry, and being coelomate. The body is segmented into head, thorax, and abdomen.
- **Annelida**: These animals are segmented but do not have a chitinous exoskeleton or jointed appendages.
- **Echinodermata**: These animals have a water vascular system and are radially symmetrical, which does not fit the characteristics given.

3. **Conclusion**:
- Based on the analysis, the only group that matches all the characteristics (triploblastic, bilateral symmetry, coelomate, chitinous exoskeleton, segmented body parts, and jointed appendages) is **Arthropoda**.

### Final Answer:
The discovered animal should be placed under the phylum **Arthropoda**.

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