ANS:A - degradation of energy.

Entropy is a measure of the disorder or randomness of a system. An increase in entropy represents an increase in the disorder or randomness of the system. In thermodynamics, this concept is closely related to the second law of thermodynamics, which states that the entropy of an isolated system tends to increase over time. When we talk about the "degradation of energy," we are referring to the dissipation or dispersion of energy into less useful forms. This concept is also related to the second law of thermodynamics. According to this law, although the total energy of a closed system remains constant, the quality of energy tends to degrade over time. This degradation occurs as energy is converted from more organized, concentrated forms (such as chemical energy or mechanical energy) into less organized, dispersed forms (such as thermal energy or kinetic energy of randomly moving particles). In summary, while an increase in entropy represents an increase in disorder or randomness within a system, the "degradation of energy" refers to the tendency of energy to disperse into less useful forms over time, as described by the second law of thermodynamics.