*Question E7A02:
What is the function of a decade counter?*  

*Correct Answer is  A: It produces one output pulse for every 10 input pulses*  

### AI Response: (may contain errors)  

A decade counter is a type of digital counter that is designed to count to ten, which corresponds to the decimal number system. Here's a breakdown of the function and why the correct answer is correct:

### Correct Answer: A
- **Explanation**: A decade counter produces one output pulse for every 10 input pulses. This means it counts from 0 to 9 (a total of 10 states) and then resets to 0, generating an output pulse each time it completes this cycle. This is useful in applications where you need to divide a frequency by 10 or count events in groups of 10.

### Why Other Choices Are Incorrect:
- **Choice B**: "It decodes a decimal number for display on a seven-segment LED display"  
  - This describes a decoder, not a counter. A decoder takes a binary input and converts it to a format suitable for driving a display, such as a seven-segment LED.

- **Choice C**: "It produces 10 output pulses for every input pulse"  
  - This is the opposite of what a decade counter does. A decade counter divides the input frequency by 10, not multiplies it.

- **Choice D**: "It decodes a binary number for display on a seven-segment LED display"  
  - Similar to Choice B, this describes a binary-to-seven-segment decoder, which is not the function of a decade counter.

### Useful Rule of Thumb:
- A decade counter is often used in digital clocks, frequency dividers, and other applications where counting in decimal (base 10) is required. It is a fundamental building block in digital electronics for counting and frequency division tasks.