A client prescribed an oral diabetic medication asks the nurse "How will I know if my blood sugar is low?" How should the nurse respond?

A. "A sign of hypoglycemia is sweating.": Sweating (diaphoresis) is a classic autonomic symptom of hypoglycemia caused by sympathetic nervous system activation. Other early signs include shakiness, palpitations, and anxiety, which alert the client to low blood glucose before neuroglycopenic symptoms develop. B. "A sign of hypoglycemia is decreased appetite.": While hyperglycemia may affect appetite, decreased appetite is not a reliable indicator of hypoglycemia. Hypoglycemia typically triggers immediate autonomic and neuroglycopenic symptoms rather than a loss of appetite. C. "A sign of hypoglycemia is insomnia.": Insomnia is not a characteristic symptom of low blood glucose. Sleep disturbances may occur with hyperglycemia or other conditions but do not indicate acute hypoglycemia. D. "A sign of hypoglycemia is a low heart rate.": Hypoglycemia generally causes tachycardia due to sympathetic activation, not bradycardia. A low heart rate would not serve as a reliable warning sign of hypoglycemia.