Which of the following will not cause nail fungus?

Excessive use of primer is primarily associated with enhancing the adhesion of nail enhancements, rather than creating conditions favorable to the development of nail fungus. Nail fungus, or onychomycosis, typically thrives in warm, moist environments (like damp shoes or sweaty conditions), as well as when there is injury to the nail bed which can make the nail more susceptible to infections. Additionally, using shared nail tools can introduce fungal spores from one person to another, leading to potential infections.

In contrast, primer is not a direct contributor to fungal growth. While excessive amounts might affect the health of the nail or the overall application, it does not create an environment conducive to the infection itself. Instead, it functions as a preparatory step in nail care and enhancements. Understanding the nature of how fungus develops is critical in maintaining nail health and practicing safe nail care.