How does a digital signal differ from an analog signal?

The digital signal is used in electronic devices.
The digital signal consists of a current that changes smoothly.
The digital signal consists of a current that changes in pulses.
The digital signal carries information.

The correct answer is: The digital signal consists of a current that changes in pulses, while the analog signal changes smoothly. A digital signal is comprised of discrete values, usually represented as ones and zeros, while an analog signal is continuous and has infinite possible values. Digital signals are commonly used in digital communication systems and computers, while analog signals are used in older technologies such as cassette tapes and vinyl records. Digital signals are resistant to noise and distortion, and can be easily stored and manipulated, making them advantageous over analog signals in many applications.