Final answer:
The b)largest island closest to the mainland would likely have the most species due to its ability to support diverse habitats and increased chances of species migration and colonization from the mainland.
Step-by-step explanation:
When considering which island would likely have the most species, we reference principles from island biogeography, which suggests that both the size of the island and its distance from the mainland are critical factors. Larger islands tend to have more resources, varied habitats, and therefore, can support a higher number of species. Proximity to the mainland also affects an island's biodiversity; islands closer to the mainland have higher rates of species migration and potentially colonization from the mainland. Consequently, the largest island closest to the mainland (option b) would likely have the most species due to its extensive area allowing for more habitats and niches and its ease of access for new species.
According to island biogeography and examples from past extinctions, smaller and more remote islands support fewer species and have higher extinction rates. This is due to lower immigration rates, reduced geographical diversity, and smaller population sizes, which increase the likelihood of extinction through processes such as genetic drift.