Read the following statements carefully and identify X, Y and Z.
X : Hard as stones, used to cook food and to produce electricity in thermal power plants
Y : A petroleum product, used in place of coal tar for metalling the roads
Z: A pure form of carbon, used in the manufacture of steel and in the extraction of many metals

Options

A. X-Coal , Y-Bitumen , Z-Coke
B. X-Coal tar , Y-Coal , Z-Paraffin wax
C. X-Coal tar , Y-Diesel , Z-Coke
D. X-Coke , Y-Bitumen , Z-Coal

Answer

To solve the question, we need to identify the substances X, Y, and Z based on the given descriptions.

### Step-by-Step Solution:

1. **Identify X:**
- The statement describes X as "hard as stones, used to cook food and to produce electricity in thermal power plants."
- **Analysis:** This description fits coal, which is a hard, black rock-like substance. Coal is commonly used as a fuel for cooking and is also burned in thermal power plants to generate electricity.
- **Conclusion:** Therefore, **X = Coal**.

2. **Identify Y:**
- The statement describes Y as "a petroleum product, used in place of coal tar for metalling the roads."
- **Analysis:** The substance that is commonly used in place of coal tar for road construction is bitumen, which is derived from petroleum. Bitumen is a viscous, sticky substance that is used for paving roads.
- **Conclusion:** Therefore, **Y = Bitumen**.

3. **Identify Z:**
- The statement describes Z as "a pure form of carbon, used in the manufacture of steel and in the extraction of many metals."
- **Analysis:** The pure form of carbon that is primarily used in steel manufacturing is coke. Coke is produced from coal and is used in the smelting process to extract metals from their ores.
- **Conclusion:** Therefore, **Z = Coke**.

### Final Answers:
- **X = Coal**
- **Y = Bitumen**
- **Z = Coke**