*Question G7B04:
In a Class A amplifier, what percentage of the time does the amplifying device conduct?*  

*Correct Answer is  A: 100%*  

### AI Response: (may contain errors)  

In a Class A amplifier, the amplifying device conducts for the entire cycle of the input signal. This means it is active 100% of the time.

### Explanation:

1. **Correct Answer: 100% (Choice A)**
   - A Class A amplifier is designed to conduct over the entire 360 degrees of the input signal cycle. This means the device is always on and amplifying, regardless of the input signal's phase. This continuous operation ensures low distortion and high linearity, which is why it conducts 100% of the time.

2. **Why Other Choices Are Incorrect:**
   - **More than 50% but less than 100% (Choice B):** This describes a Class AB amplifier, which conducts for more than half but not the entire cycle.
   - **50% (Choice C):** This is characteristic of a Class B amplifier, which conducts for exactly half of the input signal cycle (180 degrees).
   - **Less than 50% (Choice D):** This describes a Class C amplifier, which conducts for less than half of the input signal cycle, typically used for high-efficiency RF amplification.

### Key Points:
- **Class A Amplifier:** Conducts 100% of the time, providing high fidelity at the cost of efficiency.
- **Class B Amplifier:** Conducts 50% of the time, used for push-pull configurations to improve efficiency.
- **Class AB Amplifier:** Conducts more than 50% but less than 100%, balancing efficiency and linearity.
- **Class C Amplifier:** Conducts less than 50%, used for high-efficiency RF applications.

Understanding these characteristics helps in identifying the correct operation mode of different amplifier classes.