The Nurse Is Instructing a Patient on the Self-Instillation of Eye

The nurse is instructing a patient on the self-instillation of eye drops for acute conjunctivitis. What is the most important step for the nurse to teach this patient?

A) proper hand hygiene before instilling the drops
B) rub the eyes only when necessary
C) reuse cotton swabs as needed
D) insert contact lenses after the eye drops have been instilled