Which scenario is an example of the effect of a limiting factor?

The scenario of an area lacking sufficient water for plant growth exemplifies the effect of a limiting factor because it highlights how the availability of a critical resource directly impacts the survival and growth of organisms in that environment. In ecological terms, a limiting factor can be any resource or condition that restricts the growth, reproduction, or distribution of a population. Water is a fundamental resource for plants, and its scarcity can inhibit their ability to photosynthesize, grow, and reproduce, leading to decreased plant populations in that area.

By contrast, a population thriving in a rich environment does not illustrate a limiting factor, as the necessary resources are abundantly available. A species adapting to new habitats more closely relates to evolutionary processes and resilience rather than immediate limitations imposed by environmental conditions. Lastly, an increase in biodiversity due to competition emphasizes interactions between species and does not specifically address the constraints posed by limited resources or environmental factors. Therefore, the importance of water availability in scenario B effectively demonstrates how limiting factors can fundamentally shape ecological dynamics.