Final answer:
Cryptococcus neoformans var. gattii comprises serotypes B and C, and represents a significant fungal pathogen known for its capsule as a virulence factor. It causes severe infections including cryptococcal meningitis, especially in immunocompromised individuals.
Step-by-step explanation:
Cryptococcus neoformans var. gattii comprises serotypes B and C.
Cryptococcus neoformans is a significant fungal pathogen that can cause serious infections like cryptococcal meningitis, primarily affecting immunocompromised individuals such as AIDS patients. It exhibits a polysaccharide capsule that is a major virulence factor, providing resistance to phagocytosis. In nature, C. neoformans is commonly associated with pigeon droppings, while Cryptococcus gattii is found in subtropical and tropical regions and has been known to cause fatal illnesses in North America
. Regarding its variety, Cryptococcus neoformans var. gattii is divided into serotypes, each designated by different letters, indicating the presence of distinct antigens that can change or undergo antigenic variation to evade the host's immune system. The correct answer to the question of which serotypes comprise Cryptococcus neoformans var. gattii is B and C, indicating a specific grouping of this fungal pathogen's varieties based on their antigenic properties.