**Core Concept**
Preoperative medication in thyrotoxicosis aims to reduce thyroid hormone levels, alleviate symptoms, and minimize the risk of thyroid storm during surgery. This is crucial for patients undergoing thyroid surgery, as high levels of thyroid hormones can increase the risk of complications.

**Why the Correct Answer is Right**
The primary goal of preoperative medication in thyrotoxicosis is to decrease thyroid hormone production and release. Beta-blockers like propranolol are used to control symptoms such as tachycardia, tremors, and anxiety. Antithyroid medications like methimazole or propylthiouracil inhibit thyroid hormone synthesis by blocking the enzyme thyroid peroxidase (TPO). Additionally, iodine can be used to inhibit the release of preformed thyroid hormones.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because antithyroid medications like methimazole or propylthiouracil are indeed used in preoperative medication of thyrotoxicosis.
**Option B:** This option is incorrect because beta-blockers like propranolol are commonly used in the preoperative medication of thyrotoxicosis to control symptoms.
**Option C:** This option is incorrect because potassium iodide is used in the preoperative medication of thyrotoxicosis to inhibit the release of preformed thyroid hormones.

**Clinical Pearl / High-Yield Fact**
It's essential to note that the timing and dosage of preoperative medication in thyrotoxicosis should be carefully managed by an endocrinologist or a surgeon to minimize the risk of thyroid storm.

**Correct Answer: D. Potassium iodide is used in the preoperative management of hyperthyroidism but not commonly as a preoperative medication of thyrotoxicosis.**