The correct answer is C, "Mucormycosis," as it is the infectious disease associated with environmental fungi. According to the Certification Board of Infection Control and Epidemiology (CBIC) guidelines, mucormycosis is caused by fungi belonging to the order Mucorales, which are commonly found in the environment, including soil, decaying organic matter, and contaminated water. These fungi can become opportunistic pathogens, particularly in immunocompromised individuals, leading to severe infections such as rhinocerebral, pulmonary, or cutaneous mucormycosis (CBIC Practice Analysis, 2022, Domain I: Identification of Infectious Disease Processes, Competency 1.1 - Identify infectious disease processes). Environmental exposure, such as inhalation of fungal spores or contact with contaminated materials, is a primary mode of transmission, making it directly linked to environmental fungi.

Option A (Listeriosis) is caused by the bacterium Listeria monocytogenes, typically associated with contaminated food products (e.g., unpasteurized dairy or deli meats) rather than environmental fungi. Option B (Hantavirus) is a viral infection transmitted through contact with rodent excreta, not fungi, and is linked to environmental reservoirs like rodent-infested areas. Option D (Campylobacter) is a bacterial infection caused by Campylobacter species, often associated with undercooked poultry or contaminated water, and is not related to fungi.

The association of mucormycosis with environmental fungi underscores the importance of infection prevention strategies, such as controlling environmental contamination and protecting vulnerable patients, which aligns with CBIC’s focus on identifying and mitigating risks from infectious agents in healthcare settings (CBIC Practice Analysis, 2022, Domain III: Infection Prevention and Control, Competency 3.2 - Implement measures to prevent transmission of infectious agents). This knowledge is critical for infection preventionists to guide environmental cleaning and patient care protocols.