A nurse is reviewing the laboratory results of a patient who is at risk for developing diabetes mellitus. Which of the following results indicates the patient meets the criteria for diagnosis of diabetes mellitus?

Choice A reason: An HbA1c of 5.5% is within the normal range. Diabetes is diagnosed with an HbA1c ≥ 6.5%. Choice B reason: A fasting blood glucose level ≥ 126 mg/dL confirms a diagnosis of diabetes. A value of 155 mg/dL meets this criterion. Choice C reason: A 2-hour blood glucose level ≥ 200 mg/dL during an oral glucose tolerance test is diagnostic. A value of 170 mg/dL is elevated but does not meet the threshold for diagnosis. Choice D reason: A random blood glucose ≥ 200 mg/dL with symptoms of hyperglycemia is diagnostic. A value of 180 mg/dL is elevated but not diagnostic on its own.