Arthropoda is characterised by

Options

A. Triploblastic, bilateral symmetery and abdominal appendages
B. Bilateral symmetry and pair of wings
C. Acoelomate and radial symmetry
D. Exoskeleton, metameric segmentation and jointed appendages

Explanation

### Step-by-Step Solution:

1. **Understanding the Phylum Arthropoda**:
- The term "Arthropoda" is derived from the Greek words "arthros" meaning jointed and "poda" meaning feet or appendages. This indicates that members of this phylum have jointed appendages.

2. **Key Characteristics of Arthropoda**:
- **Jointed Appendages**: Arthropods possess appendages that are segmented and jointed, allowing for a wide range of movement.
- **Exoskeleton**: They have an external skeleton made of chitin, which provides protection and structural support.
- **Metameric Segmentation**: Their bodies are segmented, which is evident in the arrangement of their body parts.
- **Triploblastic**: Arthropods are triploblastic, meaning they develop from three germ layers: ectoderm, mesoderm, and endoderm.
- **Bilateral Symmetry**: They exhibit bilateral symmetry, meaning their body can be divided into two mirror-image halves.

3. **Evaluating the Options**:
- **Option 1**: "Triploblastic" - This is correct as arthropods are indeed triploblastic.
- **Option 2**: "Bilateral symmetry and pair of wings" - This is incorrect as not all arthropods have wings, and while they do exhibit bilateral symmetry, this option is misleading.
- **Option 3**: "Coelomate and radial symmetry" - This is incorrect because arthropods are not coelomates; they are actually protostomes with a reduced coelom, and they do not exhibit radial symmetry.
- **Option 4**: "Exoskeleton, metameric segmentation, and jointed appendages" - This option correctly describes the key characteristics of arthropods.

4. **Conclusion**:
- The correct characterization of Arthropoda includes the presence of an exoskeleton, metameric segmentation, and jointed appendages.

### Final Answer:
Arthropoda is characterized by an exoskeleton, metameric segmentation, and jointed appendages.

---