Quantum key distribution is described as delivering enormously long keys to communication partners.

• A. True
• B. False
• C. Not specified
• D. Ambiguous

Answer: (A)

Quantum key distribution is about creating a shared secret key with information-theoretic security by exchanging quantum states and applying post-processing to distill the key. The protocol does not fix the key length in advance; you can generate as much key material as you need by running the session longer. In practice, you accumulate longer keys over time, with security guaranteed regardless of an attacker’s computational power. That’s why QKD is described as delivering enormously long keys to communication partners—the length isn’t capped by the protocol itself, only by physical factors like channel loss and device performance. So the statement is true.