*Question E7A10:
What is a truth table?*  

*Correct Answer is  B: A list of inputs and corresponding outputs for a digital device*  

### AI Response: (may contain errors)  

A truth table is a fundamental concept in digital electronics used to describe the behavior of a digital device or logic gate. Here's a breakdown of the correct answer and why the other choices are incorrect:

1. **Correct Answer: B - A list of inputs and corresponding outputs for a digital device**

   - A truth table systematically lists all possible combinations of inputs to a digital device and the resulting outputs. It is used to define the function of logic gates and circuits by showing how the output changes based on different input values.
   - For example, a truth table for a simple AND gate with two inputs, $A$ and $B$, would look like this:

     | A | B | Output |
     |---|---|--------|
     | 0 | 0 |   0    |
     | 0 | 1 |   0    |
     | 1 | 0 |   0    |
     | 1 | 1 |   1    |

   - This table shows that the output is only true (1) when both inputs $A$ and $B$ are true (1).

2. **Why the other choices are incorrect:**

   - **Choice A: A list of inputs and corresponding outputs for an op-amp**
     - An operational amplifier (op-amp) is an analog device, not a digital one. Truth tables are not used to describe the behavior of op-amps, as they deal with continuous voltage levels rather than discrete logic levels.

   - **Choice C: A diagram showing logic states when the digital gate output is true**
     - This choice describes a specific condition or state diagram rather than a comprehensive truth table. A truth table includes all possible input combinations, not just those that result in a true output.

   - **Choice D: A table of logic symbols that indicate the logic states of an op-amp**
     - Again, op-amps are analog devices, and logic symbols are not used to describe their states. Logic symbols are used in digital electronics to represent logic gates, not op-amps.

In summary, a truth table is a tool used in digital electronics to map out all possible input combinations and their corresponding outputs for a digital device, making it essential for understanding and designing digital circuits.