Which concept is defined as randomness or disorder in a system?

• A. Entropy
• B. Genetic counseling
• C. Positive reinforcement
• D. Consent

Answer: (A)

Entropy is the measure of randomness or disorder in a system. In physics, it describes how energy becomes more dispersed and how orderly arrangements give way to greater disorder as processes unfold; the second law of thermodynamics states that the entropy of an isolated system tends to increase over time, meaning more energy is unavailable to do work. In information theory, entropy quantifies the unpredictability or information content of a message—the more unpredictable the data, the higher the entropy. This concept directly captures the idea of randomness in a system, making it the best fit. The other terms refer to unrelated ideas: genetic counseling involves assessing genetic risk and supporting families, positive reinforcement is a behavior-change technique, and consent is about agreeing to participate in treatment or research.