Which of the following correctly defines adaptive radiation?

Adaptive radiation refers specifically to the process by which organisms diversify rapidly into a wide variety of forms to adapt to specific ecological niches. This typically occurs when a species encounters new environments or ecological opportunities, allowing for the emergence of multiple species from a common ancestor. These new species evolve distinct adaptations that help them thrive in their respective niches, which can include variations in feeding strategies, reproductive traits, or physical characteristics.

This process is often observed in island ecosystems or after major extinction events when organisms face less competition and available resources rise. The diversification is driven by natural selection, where advantageous traits increase the likelihood of survival and reproduction in different environments. As a result, adaptive radiation is a major mechanism of evolutionary change and biodiversity.