`{:("List - I","List - II"),("A) Crystal defect","1) Amorphous"),("B) Carborundum","2) Frenkel"),("C) Quartz glass","3) Covalent crystal"):}`
The correct match is

Options

A. `{:(A,B,C),(3,1,2):}`
B. `{:(A,B,C),(2,1,3):}`
C. `{:(A,B,C),(2,3,1):}`
D. `{:(A,B,C),(1,2,3):}`

Answer

To solve the matching question between List - I and List - II, we will analyze each item in List - I and find the correct corresponding item in List - II.

### Step-by-Step Solution:

1. **Identify the first item in List - I: Crystal defect**
- A crystal defect refers to imperfections in the regular arrangement of atoms in a crystal lattice. One common type of defect is the **Frenkel defect**, where an atom or ion is missing from its lattice site and occupies an interstitial position.
- Therefore, we can match **Crystal defect (A)** with **Frenkel (2)**.

2. **Identify the second item in List - I: Carborundum**
- Carborundum is the common name for silicon carbide (SiC). It is known for its hardness and is classified as a **covalent crystal** because of the strong covalent bonds between silicon and carbon atoms.
- Thus, we can match **Carborundum (B)** with **Covalent crystal (3)**.

3. **Identify the third item in List - I: Quartz glass**
- Quartz glass, also known as fused silica, is primarily composed of silicon dioxide (SiO2). It does not have a long-range ordered structure, making it an **amorphous** substance.
- Hence, we can match **Quartz glass (C)** with **Amorphous (1)**.

### Final Matches:
- A matches with 2 (Crystal defect - Frenkel)
- B matches with 3 (Carborundum - Covalent crystal)
- C matches with 1 (Quartz glass - Amorphous)

### Conclusion:
The correct matches are:
- A) Crystal defect → 2) Frenkel
- B) Carborundum → 3) Covalent crystal
- C) Quartz glass → 1) Amorphous

Thus, the final answer is:
**A - 2, B - 3, C - 1**