Which of the following statements about digital signals is true?

• A. They are less reliable than analog signals
• B. They can be easily modified during transmission
• C. They are immune to interference
• D. They can only represent sound data

Answer: (C)

Digital signals are characterized by their ability to maintain integrity and clarity during transmission, making them more reliable compared to analog signals. This robustness extends their immunity to various types of interference, such as electrical noise and distortions that can occur in transmission mediums. The binary nature of digital data—where information is represented in discrete values (0s and 1s)—allows for more accurate replication and error correction compared to analog signals, which can degrade over distances and become susceptible to interference.

In contrast, the other statements do not accurately represent the characteristics of digital signals. For instance, while digital signals can undergo changes in certain contexts, they are typically more resistant to such modifications when transmitted correctly. Additionally, digital signals are not limited to sound data; they can represent a wide variety of data types, including images, text, and video, highlighting their versatility in digital communication.