*Question E8A02:
Which of the following is a type of analog-to-digital conversion?*  

*Correct Answer is  A: Successive approximation*  

### AI Response: (may contain errors)  

The correct answer to the question about types of analog-to-digital conversion is **A: Successive approximation**. Here's a breakdown of why this is the correct choice and why the others are not:

### Why Successive Approximation is Correct:
- **Successive approximation** is a method used in analog-to-digital converters (ADCs) to convert an analog signal into a digital signal. 
- It works by comparing the input voltage to a reference voltage and adjusting a binary number until it matches the input voltage. This method is efficient and widely used in many ADC applications.

### Why the Other Choices are Incorrect:
- **B: Harmonic regeneration**  
  - This refers to a technique used in radio receivers to enhance the selectivity and sensitivity of the receiver by regenerating harmonic frequencies. It is not related to analog-to-digital conversion.

- **C: Level shifting**  
  - Level shifting is a technique used to change the voltage levels of signals, often to match the input and output levels of different devices. It does not involve converting analog signals to digital.

- **D: Phase reversal**  
  - Phase reversal is a technique used in signal processing to invert the phase of a signal. It does not pertain to the process of converting analog signals to digital signals.

### Summary:
- **Correct Answer**: A: Successive approximation (a method of ADC)
- **Incorrect Answers**: 
  - B: Harmonic regeneration (related to radio receivers)
  - C: Level shifting (voltage level adjustment)
  - D: Phase reversal (signal phase inversion)

Understanding these concepts will help you in the Extra Class exam and in practical applications of radio technology.