A solid substance 'A' is very hard and electrical insulator both in the solid state as well as in molten state. It has also very high melting point. Is the solid metal like silver or network solid like silicon carbide (SiC) ?

Explanation

To determine whether the solid substance 'A' is a metal like silver or a network solid like silicon carbide (SiC), we can analyze the properties given in the question step by step.

### Step 1: Analyze the hardness of substance 'A'
- The question states that substance 'A' is very hard.
- Metals like silver are generally malleable and ductile, which means they are not as hard as network solids.
- Network solids, such as silicon carbide, are known for their hardness due to the strong covalent bonds that hold the atoms together.

**Hint:** Consider the general properties of metals versus network solids when evaluating hardness.
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