Identify the correct pair:

Options

A. Radially symmetrical - Coelenterates
B. Asymmetrical - Echinodermates
C. Bilaterally symmetrical - sponges
D. Biradially symmetrical - Platyhelminthes.

Answer

To solve the question "Identify the correct pair," we need to evaluate each option provided and determine if the symmetry described matches the organism mentioned.

### Step-by-Step Solution:

1. **Evaluate Option A: Radial-symmetrical Cylindrates**
- Cylindrates (more commonly known as Cnidarians) are indeed radially symmetrical. They include organisms like jellyfish, corals, and sea anemones.
- **Conclusion**: This option is correct.

2. **Evaluate Option B: Asymmetrical Echinodermates**
- Echinoderms (like starfish and sea urchins) exhibit bilateral symmetry in their larval stage, but as adults, they display pentaradial symmetry. Therefore, they are not asymmetrical.
- **Conclusion**: This option is incorrect.

3. **Evaluate Option C: Bilateral-symmetrical Sponges**
- Sponges belong to the phylum Porifera and are known for their asymmetrical body plan. They do not exhibit bilateral symmetry.
- **Conclusion**: This option is incorrect.

4. **Evaluate Option D: Radially-symmetrical Platyhelminth**
- Platyhelminthes (flatworms) are bilaterally symmetrical, not radially symmetrical.
- **Conclusion**: This option is incorrect.

### Final Answer:
The correct pair is **Option A: Radial-symmetrical Cylindrates**.