Which of the following would be a reason to apply a topical anesthetic?

Applying a topical anesthetic is primarily designed to numb the mucous membranes and tissues in the mouth, which can be particularly beneficial in reducing the gag reflex. By providing localized numbness, a topical anesthetic helps patients feel more comfortable during dental procedures that may otherwise elicit gagging responses, such as during the impression-taking process or when using certain devices like retractors. This enhancement of patient comfort can lead to a smoother, more efficient appointment, thereby allowing the clinician to perform procedures without the interruption that can be caused by gagging.

While there are other factors that topical anesthetics might influence, such as potentially aiding in the psychological comfort of the patient or providing a degree of pain management during minor procedures, the primary reason for its application in this context closely aligns with the goal of preventing gagging reactions.