Levothyroxine sodium is prescribed for a client with hypothyroidism. The nurse should instruct the client to report which symptom because it indicates that the client is taking too much levothyroxine sodium?

A. Constipation is more indicative of hypothyroidism rather than an excess of levothyroxine. B. Decreased appetite could be related to hypothyroidism or other factors, but it is not a primary symptom of levothyroxine overdose. C. Restlessness is a sign of hyperthyroidism or excessive levothyroxine, indicating that the dosage might be too high. D. Intolerance to cold is usually associated with hypothyroidism, not an excess of levothyroxine.