A nurse is teaching a client how to draw up regular insulin and NPH insulin into the same syringe. Which of the following instructions should the nurse include?

A. Discard regular insulin that appears cloudy: Regular insulin (short-acting) should always be clear and colorless. If it appears cloudy or discolored, it may be contaminated or have lost potency and must be discarded. (NPH insulin is normally cloudy). B. Shake the NPH insulin until it is well mixed: Insulin vials should never be shaken, as this creates air bubbles that can alter the dose volume. The vial should be gently rolled between the palms to mix the suspension. C. Draw up the NPH insulin into the syringe first: When mixing insulins, the standard procedure is "Clear before Cloudy" (Regular before NPH). This prevents the cloudy NPH from contaminating the clear Regular vial. If NPH gets into the Regular vial, it ruins the fast-acting properties of the entire vial. D. Inject air into the regular insulin first: The correct order for air injection is: 1) Inject air into NPH (cloudy), 2) Inject air into Regular (clear), 3) Draw Regular, 4) Draw NPH.