Final answer:
The assertion that a fungal test may be used to diagnose cystic fibrosis is false. Cystic fibrosis is diagnosed through genetic or sweat chloride testing, not fungal tests.
Step-by-step explanation:
It is false that a fungal test may be used to diagnose cystic fibrosis. Cystic fibrosis is a genetic disorder that affects the lungs and other organs, leading to thickened mucus that can trap bacteria and other pathogens such as Pseudomonas aeruginosa. While fungal infections can occur in individuals with cystic fibrosis, and certain fungi like Coccidioides immitis and Cryptococcus can be diagnosed using specific tests, the condition of cystic fibrosis itself is diagnosed using a different set of tests focused on detecting genetic mutations or abnormal sweat chloride levels.