The practical nurse (PN) is observing a client self-administering the noon dose of subcutaneous insulin. What step of the injection technique should the practical nurse (PN) reteach?

A. Selects the same site that was used for the previous injection: The PN should reteach this step because insulin injection sites must be rotated to prevent lipohypertrophy and uneven absorption. Repeated use of the same site can lead to tissue thickening, altered insulin uptake, and unpredictable glucose control. B. Inserts the needle at a 90 degree angle to the skin surface: A 90-degree angle is appropriate for most adults using short insulin needles, ensuring proper subcutaneous delivery. The angle may be adjusted only for very thin clients or when using longer needles. C. Uses a circular action when applying an alcohol pad to the site: Cleaning the site in a circular motion from the center outward helps reduce bacterial contamination before injection. This technique is correct and should continue to be reinforced. D. Injects air into the insulin vial to displace the dose: Injecting air equal to the insulin dose into the vial helps maintain pressure balance and ensures accurate dose withdrawal. This is a proper and necessary step in insulin preparation.