What is one reason why overhead sprinklers might lead to disease spread among plants?

Overhead sprinklers lead to disease spread among plants primarily because they wet the foliage. When water is applied from above, it can create a humid environment on the leaves and other plant surfaces. This moisture can foster conditions that are favorable for various fungal and bacterial diseases to thrive. Many plant pathogens, particularly fungi, require a wet or moist environment to germinate and infect plant tissues. Therefore, the presence of water on the foliage can significantly increase the risk of disease transmission among plants. In contrast, other options such as cost or monitoring requirements do not directly relate to the disease spread mechanism.