Basic definition – What is a digital-to-analog converter (DAC)? Choose the option that correctly describes the role of a DAC in everyday systems such as audio playback.

Introduction / Context:
Digital systems represent information as numbers. To drive real-world devices such as speakers, motors, or displays, we often need an analog signal. A digital-to-analog converter (DAC) performs precisely this function.

Given Data / Assumptions:

• Audio CDs, media players, and computers store audio as digital samples.
• Speakers require an analog voltage or current waveform.
• The question seeks a correct everyday description.

Concept / Approach:
A DAC accepts a digital code and outputs an analog level proportional to that code. In audio, rapid updates of the DAC reconstruct a time-varying waveform which is then filtered and amplified to drive speakers. The principle applies to many domains, including control systems and instrumentation.

Step-by-Step Solution:
Digital word → DAC input.DAC outputs an analog level corresponding to the code and reference.Reconstruction filter removes sampling images, yielding smooth audio.Amplifier drives the load with the recovered analog waveform.

Verification / Alternative check:
Block diagrams of CD/DVD/streaming players show: storage/decoder → digital filter → DAC → analog filter → amplifier → speaker.

Why Other Options Are Wrong:
Option B is misleading; DACs do not exist to “always” make things simpler.

Option C describes storage, not conversion.

Option D is a function of inverters or power electronics, not a DAC.

Option E describes an ADC (the opposite direction).

Common Pitfalls:
Confusing sample rate with audio frequency content; reconstruction filtering is essential to avoid aliasing images in the output.

Final Answer:
It takes the digital information from an audio CD and converts it to a usable form.