Three major causes of biodiversity losses:
1. Habitat destruction: Destruction of natural habitats, like deforestation and urbanization, leads to the loss of biodiversity by reducing the area available for species to live and reproduce.
2. Pollution: Pollution of air, water, and soil adversely affects many species, disrupting ecosystems and causing species to either migrate or go extinct.
3. Climate change: Global warming alters habitats and climate patterns, forcing species to adapt, migrate, or face extinction due to unsuitable environmental conditions.
Study the pie chart given below, representing the global biodiversity and proportionate number of species of major taxa.

Answer the following questions:
[a] Identify 'X' and 'Y' in the given pie chart.
[b] Which one of the two 'X' or 'Y' is the most species-rich taxonomic group and by what percentage?
[c] Name the level of Biodiversity represented by the following: