Which of the following is NOT one of the five soil forming factors?

The option indicating human activity as not one of the five soil forming factors is correct because the foundational soil forming factors are generally recognized as climate, time, parent material, topography, and organisms.

These five factors work together over time to influence the formation and development of soil. Climate affects temperature and moisture availability, which are critical for the processes of weathering and organic matter development. Topography influences drainage and sun exposure, which also impact soil formation processes. Time allows for the cumulative effects of weathering and biological activity to alter and develop soil profiles.

While human activity can impact soil properties and lead to changes in soil condition or health—such as through agriculture or urban development—it's not classified as a fundamental soil forming factor in the same context as the others. Human activity plays a role in modifying existing soils but does not inherently contribute to the soil formation processes over geological timescales. This distinction clarifies why it is not considered one of the core factors governing the natural formation of soil.