What does a Kraus representation describe?

Question: What does a Kraus representation describe in quantum information? A) A classical database index B) A general quantum channel, including noisy non-unitary evolution C) A perfect reversible gate only D) A coupling map visualization Correct: B Explanation: Kraus operators represent general quantum operations, including noisy processes that cannot be described by a single unitary matrix. They are used in noise modeling and open quantum systems. Topic: quantum computing / quantum channels / Kraus operators