**Core Concept**
Mifepristone is a potent glucocorticoid receptor antagonist and progesterone receptor antagonist. It is primarily used in medical abortion, specifically for the termination of early pregnancy, and also has therapeutic applications in managing conditions such as Cushing's syndrome.

**Why the Correct Answer is Right**
Mifepristone works by binding to the progesterone receptor, thereby blocking the action of progesterone, which is essential for maintaining pregnancy. By inhibiting progesterone's action, mifepristone induces uterine contractions, leading to the expulsion of the embryo or fetus. This mechanism is critical in the medical management of early pregnancy termination.

**Why Each Wrong Option is Incorrect**
**Option A:** Mifepristone is not primarily used as an antiemetic or to treat nausea and vomiting. Although it may have some off-target effects, its primary indication is not related to gastrointestinal symptoms.
**Option B:** Cushing's syndrome is a condition where there is excess cortisol production, and mifepristone is used to manage this condition by blocking the action of cortisol on its receptors. However, it is not the only treatment option for Cushing's syndrome.
**Option C:** There is no strong evidence to support the use of mifepristone as a treatment for hypertension. While it may have some effects on blood pressure due to its anti-glucocorticoid activity, it is not a recommended treatment for hypertension.

**Clinical Pearl / High-Yield Fact**
Mifepristone is often used in combination with misoprostol, a prostaglandin analogue, to enhance its efficacy in medical abortion. This combination takes advantage of the synergistic effects of both drugs to induce uterine contractions and expel the embryo or fetus.

**Correct Answer: C. Cushing's syndrome. Mifepristone is used in the management of Cushing's syndrome by blocking the action of cortisol on its receptors.**