Petrology is study of

Options

A. Petroleum bearing rocks
B. Various aspects of utilisation of crude oil
C. Rocks
D. Crust of earth.

Answer

**Step-by-Step Solution:**

1. **Understanding Petrology**: Petrology is defined as the scientific study of rocks. It encompasses various types of rocks and their formation processes.

2. **Types of Rocks**: Petrology primarily focuses on three main types of rocks:
- **Igneous Rocks**: Formed from the solidification of molten material (magma or lava).
- **Metamorphic Rocks**: Formed from the alteration of existing rocks due to heat, pressure, or chemically active fluids.
- **Sedimentary Rocks**: Formed from the accumulation and compaction of mineral and organic particles.

3. **Processes Involved**: In addition to studying the types of rocks, petrology also involves understanding the processes that lead to the formation and transformation of these rocks.

4. **Eliminating Incorrect Options**:
- The option stating "petroleum bearing rocks" is incorrect because petrology is not limited to petroleum-related studies.
- The option regarding "various aspects of utilization of crude oil" is also incorrect as it pertains to petroleum engineering rather than petrology.
- The option stating "crust of earth" is too broad and does not specifically define petrology.

5. **Conclusion**: Therefore, the correct answer to the question "Petrology is the study of" is that it is the study of rocks, which includes igneous, metamorphic, and sedimentary rocks, along with the processes that form and transform them.

**Final Answer**: Petrology is the study of rocks.

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