The transfer characteristics of a base biased transistor has the operation regions, namely, cutoff, active region and saturation region. For using the transistor as an amplifier it has to operate in the

Options

A. active region
B. cutoff region
C. saturation region
D. cutoff and saturation

Explanation

To determine the operation region of a base biased transistor when used as an amplifier, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Operation Regions**:
- A transistor has three main operation regions: cutoff, active, and saturation.
- In the cutoff region, the transistor is off and does not conduct current.
- In the saturation region, the transistor is fully on and conducts maximum current.
- The active region is where the transistor can amplify signals.

2. **Identify the Purpose of Each Region**:
- The cutoff region is used when the transistor is acting as a switch in the off state.
- The saturation region is used when the transistor is acting as a switch in the on state.
- The active region is where the transistor can amplify input signals.

3. **Determine the Required Region for Amplification**:
- For a transistor to function as an amplifier, it must operate in the active region.
- In this region, the transistor can respond to small changes in input voltage and produce a larger output voltage.

4. **Conclusion**:
- Therefore, for a base biased transistor to be used as an amplifier, it must be operated in the **active region**.

### Final Answer:
A base biased transistor operates as an amplifier in the **active region**.

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