The study of coelenterates is known as

Options

A. Arthrology
B. Splanchnology
C. Cnidology
D. Nidology

Answer

To answer the question "The study of coelenterates is known as," we need to analyze the options provided and identify the correct term associated with the study of this specific group of organisms.

### Step-by-Step Solution:

1. **Understanding Coelenterates**: Coelenterates, also known as cnidarians, include organisms such as jellyfish, corals, and sea anemones. The study of these organisms falls under a specific branch of biology.

2. **Evaluating the Options**:
- **Option A: Arthrology**: This term refers to the study of joints. Since coelenterates are not related to joints, this option is incorrect.
- **Option B: Splanchnology**: This term pertains to the study of visceral organs, which includes digestive and reproductive systems. It does not relate to coelenterates, making this option incorrect as well.
- **Option C: Nidology**: This term is the study of bird nests. While it sounds similar to the term we are looking for, it is not related to coelenterates, so this option is also incorrect.
- **Option D: Cnidology**: This is the correct term for the study of coelenterates (cnidarians). It specifically focuses on the biology, ecology, and physiology of these organisms.

3. **Conclusion**: Based on the analysis of the options, the study of coelenterates is known as **Cnidology**.

### Final Answer:
The study of coelenterates is known as **Cnidology**.

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