A nurse is checking the laboratory results of a client who is at risk for diabetes mellitus. Which of the following laboratory results indicates to the nurse that the client is at risk for diabetes mellitus?

A. 2-hr blood glucose 132 mg/dL: A 2-hour OGTT under 140 mg/dL is considered normal; 132 mg/dL is not in the impaired-glucose-tolerance/prediabetes range. B. HbA1c 5.2%: An A1c of 5.2% is within the normal range (below prediabetes threshold). C. Fasting blood glucose 155 mg/dL: A fasting glucose ≥126 mg/dL is abnormal and indicative of diabetes (or at minimum places the client at clear risk), so 155 mg/dL is a significant abnormal result. D. Casual blood glucose 178 mg/dL: A random glucose under 200 mg/dL is high but below the usual diabetes diagnostic cutoff (≥200 mg/dL); it suggests hyperglycemia but is less definitive than an elevated fasting glucose.