What indicates a risk of developing hyperthyroidism?

The correct choice indicates a risk of developing hyperthyroidism because nervousness is a common symptom associated with an overactive thyroid. Hyperthyroidism results in an increased production of thyroid hormones, which can lead to heightened metabolic activity and symptoms such as anxiety, irritability, and nervousness. These symptoms stem from the thyroid hormones' effects on the body's metabolism and nervous system.

On the other hand, weight gain, cold sensitivity, and hair loss are typically associated with hypothyroidism, where there is an underproduction of thyroid hormones. In this condition, metabolic processes slow down, leading to weight gain, decreased tolerance to cold, and potential hair loss due to reduced metabolic support to hair follicles. Therefore, while these symptoms indicate thyroid dysfunction, they are more aligned with hypothyroidism rather than hyperthyroidism.