Which scenario illustrates the second law of thermodynamics?

The second law of thermodynamics states that in any energy exchange, if no energy enters or leaves the system, the potential energy will always decrease over time. This leads to an increase in entropy, which is a measure of disorder or randomness in a system. In the context of the provided scenarios, the situation where a baby brother scatters toys all over the floor exemplifies this principle perfectly.

When the toys are scattered, the overall organization and neatness of the space diminish, resulting in greater disorder—an increase in entropy. The act of scattering toys represents a natural progression towards disorder, as it requires no external energy and occurs spontaneously. This scenario illustrates the tendency of systems to move towards a state of greater disorder over time, demonstrating the essence of the second law of thermodynamics. The other scenarios involve a state of order or cleanliness, which would not align with the concept of increasing entropy.