**Core Concept**
Total thyroidectomy is a surgical procedure that involves the removal of the entire thyroid gland. This operation can lead to various complications, some of which are life-threatening. The underlying principle being tested is the knowledge of potential postoperative complications following this procedure.

**Why the Correct Answer is Right**
The complications of total thyroidectomy can be broadly categorized into immediate and late complications. Immediate complications include bleeding, hematoma, respiratory distress due to recurrent laryngeal nerve injury, and hypocalcemia due to parathyroid gland damage. Late complications include hypothyroidism, vocal cord paralysis, and thyroid storm. The correct answer will be one of these well-known complications.

**Why Each Wrong Option is Incorrect**
**Option A:** *Reactive hypoglycemia* is not a known complication of total thyroidectomy. This condition is typically associated with gastric bypass surgery.
**Option B:** *Hypertension* is not a direct complication of total thyroidectomy, although patients with thyroid disease may have associated hypertension.
**Option C:** *Thyroid storm* is a known complication of total thyroidectomy, especially in patients with undiagnosed or inadequately treated hyperthyroidism.

**Clinical Pearl / High-Yield Fact**
It is crucial for surgeons and anesthesiologists to be aware of the potential complications of total thyroidectomy and have a plan in place for their management. This includes having a thorough understanding of the anatomy of the thyroid gland and its surrounding structures.

**Correct Answer: C. Thyroid storm.**