- Legionellosis (A): This is a bacterial disease caused by {Legionella} species, primarily {Legionella pneumophila}, which are waterborne pathogens.
- Giardiasis (B): This disease is caused by {Giardia lamblia}, a protist that infects the gastrointestinal tract through contaminated water or food.
Other options: - Typhoid fever (C): Typhoid fever is caused by the bacterium {Salmonella Typhi}, not a virus.
- Listeriosis (D): Listeriosis is caused by the bacterium {Listeria monocytogenes}, not a fungus.