Glass is a:

Options

A. liquid
B. solid
C. supercooled liquid
D. transparent-organic polymer

Explanation

To determine what glass is, we can analyze the options provided and the properties of glass:

### Step 1: Understand the options
The options given are:
- Liquid
- Solid
- Supercooled liquid
- Transparent
- Organic polymer

### Step 2: Analyze the properties of glass
Glass is known to be an amorphous solid. This means it does not have a definite geometric shape or a sharp melting point, unlike crystalline solids.

### Step 3: Define amorphous solids
Amorphous solids, such as glass, are often referred to as pseudo solids. They are formed from liquids through a process called supercooling, which allows them to solidify without crystallizing.

### Step 4: Identify the characteristics of glass
- **No definite shape**: Unlike crystalline solids, glass does not have a fixed geometric structure.
- **No sharp melting point**: Glass does not melt at a specific temperature but rather over a range of temperatures.
- **Isotropic nature**: The physical properties of glass, such as refractive index, are the same in all directions.

### Step 5: Choose the correct answer
Given the analysis, the best description of glass from the options provided is "supercooled liquid," as it describes the process through which glass is formed. However, it is also important to note that glass is classified as an amorphous solid.

### Conclusion
The correct answer to the question "Glass is a:" is **C. Supercooled liquid** (with the understanding that it is also an amorphous solid).

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