Tectonic is

Options

A. Study of earth's crust
B. Study of earthquakes
C. Science dealing with geothermal energy
D. Study of volcanoes.

Answer

To answer the question "Tectonic is," we will analyze the options provided and determine which one correctly defines tectonics.

### Step-by-Step Solution:

1. **Understanding Tectonics**: Tectonics refers to the study of the Earth's crust and the movements of the plates that make up the crust. This field is essential for understanding geological processes.

2. **Analyzing the Options**:
- **Option A**: The study of the Earth’s crust. This aligns with the definition of tectonics as it involves understanding the structure and movements of the Earth's crust.
- **Option B**: The study of earthquakes. This is known as seismology, which is a different field and not what tectonics primarily focuses on.
- **Option C**: The science of dealing with geothermal energy. This is related to energy studies and does not pertain directly to tectonics.
- **Option D**: The study of particular volcanoes. This is known as volcanology and is also a separate field from tectonics.

3. **Identifying the Correct Answer**: Based on the definitions and explanations provided, the correct answer is:
- **Option A**: The study of the Earth’s crust.

### Final Answer:
Tectonic is the study of the Earth’s crust.

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