Which of the following processes occur only in animals?

Options

A. Hormonal control
B. Respiration
C. Nervous control
D. Nutrition

Answer

### Step-by-Step Solution:

1. **Identify the Processes**: The question asks which processes occur only in animals. We need to evaluate different biological processes to determine their exclusivity to animals.

2. **Evaluate Hormonal Control**: Hormonal control is a process where hormones regulate various functions in organisms. However, this process is not exclusive to animals, as plants also have hormonal control mechanisms through plant hormones (e.g., auxins, gibberellins). Therefore, hormonal control cannot be the answer.

3. **Evaluate Respiration**: Respiration is a vital process for energy production in organisms. Both plants and animals perform respiration, albeit through different mechanisms (e.g., photosynthesis in plants during the day and cellular respiration in both plants and animals). Hence, respiration is not exclusive to animals.

4. **Evaluate Nervous Control**: Nervous control refers to the regulation of body functions through a nervous system. This system is primarily found in multicellular animals. While some simpler organisms (like sponges and certain microscopic organisms) lack a nervous system, more complex animals have varying degrees of nervous systems, from simple nerve nets in jellyfish to complex brains in mammals. Thus, nervous control is a process that occurs only in animals.

5. **Conclusion**: Based on the evaluation of the processes, the only process that occurs exclusively in animals is **Nervous Control**.

### Final Answer:
**Nervous Control** is the process that occurs only in animals.

---