Final answer:
The client shows an understanding of the fluticasone inhaler use by stating they will rinse their mouth after use, which is important to prevent oral thrush, a side effect of inhaled steroids.
Step-by-step explanation:
The correct statement that indicates an understanding of how to use a fluticasone inhaler is: D) "I will rinse my mouth after I use this inhaler". Fluticasone is a corticosteroid used for the long-term control of asthma, which means it helps to prevent asthma attacks rather than treat one that is already happening. The inhaler does not provide immediate relief of acute asthma symptoms; instead, it works overtime to reduce inflammation in the airways. Rinsing the mouth after using a fluticasone inhaler helps to prevent a possible side effect known as oral thrush, an infection that can occur in the mouth due to the steroid medication.