Why is digital transmission often considered more secure than analog transmission?

• A. Because it is easier to encrypt
• B. Because it is immune to interference
• C. Because it cannot be intercepted
• D. Because it requires no security measures

Answer: (A)

The key idea is that digital transmission is well-suited to applying cryptography. Data represented as bits can be encrypted with cryptographic algorithms using a key, turning it into ciphertext that looks like random data. Without the correct key, even a listener who copies the transmission can’t recover the original information. This ability to encrypt easily and robustly, along with practical key management, authentication, and integrity checks that digital systems support, is what makes digital transmission feel much more secure in practice.

Interference immunity isn’t guaranteed—digital signals can still be corrupted by noise, though error detection and correction help. The notion that it cannot be intercepted is false; any transmission can be intercepted, and security relies on encryption, not on being unhackable. The idea that no security measures are needed is also incorrect; security is a fundamental part of digital transmission, achieved primarily through encryption and related techniques.