A nurse is collecting data from a client who takes metformin for type 2 diabetes. Which of the following medications may be contraindicated for this client due its effect on blood glucose levels?

A. Prednisone is a corticosteroid that can increase blood glucose levels, potentially counteracting the effects of metformin and requiring careful monitoring. B. Acetaminophen does not significantly affect blood glucose levels and is generally safe for clients with diabetes. C. Cephalexin, an antibiotic, does not typically alter blood glucose levels and is not contraindicated with metformin. D. Lisinopril may slightly lower blood glucose in some cases but is generally safe for clients taking metformin and is not contraindicated.