What is a digital signal?

• A. A method of representing data in binary form for storage or transmission
• B. A sequence of electrical signals used in analog devices
• C. A type of signal used only in video broadcasting
• D. A form of communication that requires a physical connection

Answer: (A)

A digital signal refers to a method of representing data in binary form, which consists of discrete values—typically represented as 0s and 1s. This representation allows for efficient storage and transmission of information across various digital devices and networks. Digital signals are robust against interference, making them ideal for things like computer communications and data transmission over the internet. They can easily be processed, compressed, and encrypted, further enhancing their utility in various applications.

The other options do not accurately define a digital signal. For instance, electrical signals used in analog devices pertain to a continuous range of values rather than binary. Furthermore, digital signals are not restricted to video broadcasting; they are widely used in many forms of digital communication, including data transfer and telecommunication. Finally, while some forms of communication may require a physical connection, digital signals themselves can also be transmitted wirelessly or over various mediums, making the last option incomplete. Thus, the definition in the first choice is the most comprehensive and accurate regarding what a digital signal entails.