A nurse is reinforcing teaching about the use of an insulin aspart 70/30 pen with a client who has type 1 diabetes mellitus. Which of the following statements by the client indicates an understanding of the teaching?

A. "I will hold the pen upside-down to select the appropriate dose.": Insulin pens are designed to be held upright with the needle pointing upward when selecting the dose. Holding it upside-down can cause air bubbles to enter the cartridge and result in inaccurate dosing. Correct technique ensures the client receives the intended insulin amount. B. "I will apply a disposable needle on the cartridge.": Attaching a new disposable needle for each injection is essential to maintain sterility, prevent infection, and ensure accurate dosing. This practice also prevents needle damage and reduces the risk of insulin leakage during administration. C. "I will aspirate before injecting the insulin.": Aspiration is unnecessary with subcutaneous insulin injections and can cause tissue trauma or discomfort. Current guidelines advise inserting the needle directly into subcutaneous tissue without pulling back to check for blood. D. "I will shake the pen before injecting the insulin.": Shaking insulin aspart 70/30 can create air bubbles and compromise the insulin mixture. Instead, gently rolling the pen between the palms ensures proper mixing without introducing bubbles, preserving insulin effectiveness.