From the organisms given below, select the odd one on the basis of symmetry shown by them.

Options

A. Meandrina
B. Taenia
C. Psittacula
D. Limulus

Answer

To solve the question of identifying the odd organism based on symmetry, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Symmetry**:
- Organisms can be classified based on their symmetry into three main types:
- **Asymmetrical**: No symmetry; cannot be divided into equal halves.
- **Radial Symmetry**: Can be divided into similar halves by multiple planes passing through the center (like a circle).
- **Bilateral Symmetry**: Can be divided into two equal halves by a single plane (usually the sagittal plane).

2. **Identify the Organisms**:
- The organisms mentioned are:
- **Taenia** (tapeworm)
- **Satacula** (parrot)
- **Limulus** (king crab)
- **Beandrina** (brain coral)

3. **Determine the Symmetry of Each Organism**:
- **Taenia**: This is a flatworm and exhibits bilateral symmetry.
- **Satacula**: As a parrot, it also shows bilateral symmetry.
- **Limulus**: Known as king crab, it is also bilaterally symmetrical.
- **Beandrina**: This is a brain coral, which exhibits radial symmetry.

4. **Compare the Symmetries**:
- The first three organisms (Taenia, Satacula, Limulus) all exhibit bilateral symmetry.
- The Beandrina, on the other hand, shows radial symmetry.

5. **Identify the Odd One Out**:
- Since Beandrina is the only organism that does not exhibit bilateral symmetry, it is the odd one out.

### Conclusion:
The odd organism based on symmetry is **Beandrina** (brain coral).

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