Final answer:
A low rate of metabolism is atypical for hyperthyroidism as it usually is characterized by an increased metabolic rate due to an overactive thyroid gland. Symptoms more commonly associated with hyperthyroidism include nervousness, exophthalmos, low body weight, and tachycardia.
Step-by-step explanation:
The symptom that is atypical for hyperthyroidism among the options given is C) Low rate of metabolism. Hyperthyroidism is a condition characterized by an overactive thyroid gland, which leads to an elevated level of thyroid hormone in the blood, resulting in symptoms such as nervousness (A), exophthalmos or protruding eyes (B), low body weight due to weight loss (D), and a rapid heartbeat or tachycardia (E). A low rate of metabolism is more typically associated with hypothyroidism, where the thyroid gland is underactive, leading to symptoms like weight gain, cold sensitivity, and reduced mental activity.