The filament of a bulb is

Options

A. Conductor
B. Insulator
C. Semi-conductor
D. Both (a) and (b)

Explanation

**Step-by-Step Solution:**

1. **Understanding the Filament's Role:** The filament of a bulb is a crucial component that plays a significant role in the functioning of an electric bulb. It is responsible for converting electrical energy into light and heat energy.

2. **Material of the Filament:** The filament is typically made of a material known as Tungsten. Tungsten is chosen because it has a high melting point and can withstand the heat generated when electricity passes through it.

3. **Conductor Properties:** The filament acts as a conductor. This means it allows electric current to flow through it. However, it is important to note that while it is a conductor, it has a very high resistance.

4. **High Resistance Effect:** The high resistance of the tungsten filament is what allows it to convert electrical energy into heat and light. When electricity flows through the filament, the high resistance causes the filament to heat up, and this heat produces light.

5. **Conclusion:** Therefore, the filament of an electric bulb is a conductor made of tungsten, and its high resistance is essential for its function of converting electrical energy into heat and light energy.

**Final Answer:** The filament of a bulb is a conductor made of tungsten with high resistance.

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