Which clinical sign is associated with conjunctival epithelium and goblet cells?

The clinical sign associated with conjunctival epithelium and goblet cells is primarily epiphora. The conjunctival epithelium is responsible for the production of mucus and helps to maintain moisture in the eyes. Goblet cells, which are found in the conjunctiva, produce mucin, an important component of the tear film that contributes to eye lubrication and protection. When the conjunctiva is irritated or inflamed, it can lead to an increase in tear production and drainage, resulting in epiphora, or excessive tearing.

Epiphora can occur due to various conditions such as conjunctivitis or obstruction of tear drainage pathways, both of which can stimulate the goblet cells to produce more mucus and tears, leading to the clinical sign of watery eyes. The other options listed—corneal opacity, pupil constriction, and photophobia—are not directly associated with the activities of the conjunctival epithelium and goblet cells, as they are more related to other ocular structures and functions.