Which of the following describes a nutrient cycle?

A nutrient cycle refers specifically to the movement of nutrients through various components of an ecosystem, including the soil, water, plants, animals, and microorganisms. Nutrients such as nitrogen, phosphorus, and potassium are essential for the growth and development of organisms. They are taken up by plants from the soil and water, passed through the food web as animals eat plants and each other, and eventually returned to the environment through processes like decay and excretion.

This cycle ensures that essential nutrients are continuously available in the environment, supporting life and facilitating productivity in ecosystems. While the transfer of energy and the decay of organic matter are related processes in ecosystems, they do not encompass the full scope of how nutrients circulate and are reused. Likewise, evaporation is a critical part of the water cycle but does not pertain to the movement of nutrients. Thus, the choice that accurately reflects the concept of a nutrient cycle is the movement of nutrients through the ecosystem.