The correct option is B Hyperfunction of the thyroid
Graves disease, also called as toxic diffuse goitre or exophthalmic goitre, is an endocrine disorder, that is the most common cause of hyperthyroidism. The increased thyroid hormone production results in the symptoms and signs of hyperthyroidism. Some patients experience exophthalmos (protrusion of the eyes), with eyelid retraction, edema of tissues surrounding the eyes, double vision, and occasionally loss of vision, all of which are symptoms of a condition, known as Graves ophthalmopathy.